{ "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-2026-34526", "tracking": { "current_release_date": "2026-04-03T15:31:44.807794Z", "generator": { "date": "2026-02-17T15:00:00Z", "engine": { "name": "V.E.L.M.A", "version": "1.7" } }, "id": "CVE-2026-34526", "initial_release_date": "2026-04-01T23:02:41.791277Z", "revision_history": [ { "date": "2026-04-01T23:02:41.791277Z", "number": "1", "summary": "CVE created.| Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (2).| CWES updated (1)." }, { "date": "2026-04-01T23:02:44.433621Z", "number": "2", "summary": "NCSC Score created." }, { "date": "2026-04-02T11:35:26.105535Z", "number": "3", "summary": "NCSC Score updated." }, { "date": "2026-04-02T17:39:32.910189Z", "number": "4", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| Products connected (1).| References created (2).| CWES updated (1)." }, { "date": "2026-04-02T17:39:34.738434Z", "number": "5", "summary": "NCSC Score updated." }, { "date": "2026-04-02T18:26:47.889080Z", "number": "6", "summary": "Source created.| CVE status created. (valid)| Description created for source.| CVSS created.| References created (2).| CWES updated (1)." }, { "date": "2026-04-02T18:26:49.698858Z", "number": "7", "summary": "NCSC Score updated." }, { "date": "2026-04-02T18:48:00.289216Z", "number": "8", "summary": "Unknown change." }, { "date": "2026-04-03T15:31:27.499291Z", "number": "9", "summary": "Source connected.| CVE status created. (valid)| EPSS created." }, { "date": "2026-04-03T15:31:36.601838Z", "number": "10", "summary": "NCSC Score updated." } ], "status": "interim", "version": "10" } }, "product_tree": { "branches": [ { "branches": [ { "branches": [ { "category": "product_version_range", "name": "vers:unknown/<1.17.0", "product": { "name": "vers:unknown/<1.17.0", "product_id": "CSAFPID-5985091" } } ], "category": "product_name", "name": "SillyTavern" } ], "category": "vendor", "name": "SillyTavern" } ] }, "vulnerabilities": [ { "cve": "CVE-2026-34526", "cwe": { "id": "CWE-918", "name": "Server-Side Request Forgery (SSRF)" }, "notes": [ { "category": "description", "text": "### Details\nDistinct from CVE-2025-59159 and CVE-2026-26286 (all fixed in v1.16.0). This endpoint is still unpatched.\n\nIn `src/endpoints/search.js` line 419, the hostname is checked against `/^\\d+\\.\\d+\\.\\d+\\.\\d+$/`. This only matches literal dotted-quad IPv4 (e.g. `127.0.0.1`, `10.0.0.1`). It does not catch:\n- `localhost` (hostname, not dotted-quad)\n- `[::1]` (IPv6 loopback)\n- DNS names resolving to internal addresses (e.g. `localtest.me` -> 127.0.0.1)\n\nA separate port check (`urlObj.port !== ''`) limits exploitation to services on default ports (80/443), making this lower severity than a fully unrestricted SSRF.\n\n### PoC\n1. Start SillyTavern v1.16.0 normally\n2. Send requests to compare blocked vs bypassed (requires a valid session cookie or CSRF disabled):\n```bash\n# Blocked — dotted-quad matched by regex\ncurl -s -o /dev/null -w \"%{http_code}\" -X POST http://127.0.0.1:8000/api/search/visit \\\n -H \"Content-Type: application/json\" \\\n -d '{\"url\": \"http://127.0.0.1/\", \"html\": true}'\n# Returns: 400 (blocked)\n\n# Bypassed — \"localhost\" is not dotted-quad\ncurl -s -o /dev/null -w \"%{http_code}\" -X POST http://127.0.0.1:8000/api/search/visit \\\n -H \"Content-Type: application/json\" \\\n -d '{\"url\": \"http://localhost/\", \"html\": true}'\n# Returns: 500 (passed validation, fetch attempted, ECONNREFUSED because nothing on port 80)\n\n# Bypassed — IPv6 loopback is not dotted-quad\ncurl -s -o /dev/null -w \"%{http_code}\" -X POST http://127.0.0.1:8000/api/search/visit \\\n -H \"Content-Type: application/json\" \\\n -d '{\"url\": \"http://[::1]/\", \"html\": true}'\n# Returns: 500 (passed validation, fetch attempted)\n```\n\nThe 400 vs 500 difference confirms `localhost` and `[::1]` pass the IP check. The 500 is ECONNREFUSED (nothing listening on port 80), not a validation rejection.\n\n### Impact\nServer-side request forgery with partial restrictions. An authenticated user can force the server to fetch from internal hosts on default ports (80/443) using hostnames or IPv6 addresses that bypass the IP check. The full response body is returned. Lower severity than a fully unrestricted SSRF due to the port limitation.\n\n## Resolution\n\nThe issue was addressed in version 1.17.0 by improving IPv6 address validation", "title": "github - https://api.github.com/advisories/GHSA-wm7j-m6jm-8797" }, { "category": "description", "text": "SillyTavern is a locally installed user interface that allows users to interact with text generation large language models, image generation engines, and text-to-speech voice models. Prior to version 1.17.0, in src/endpoints/search.js, the hostname is checked against /^\\d+\\.\\d+\\.\\d+\\.\\d+$/. This only matches literal dotted-quad IPv4 (e.g. 127.0.0.1, 10.0.0.1). It does not catch: localhost (hostname, not dotted-quad), [::1] (IPv6 loopback), and DNS names resolving to internal addresses (e.g. localtest.me -> 127.0.0.1). A separate port check (urlObj.port !== '') limits exploitation to services on default ports (80/443), making this lower severity than a fully unrestricted SSRF. This issue has been patched in version 1.17.0.", "title": "cveprojectv5 - https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/34xxx/CVE-2026-34526.json" }, { "category": "description", "text": "SillyTavern is a locally installed user interface that allows users to interact with text generation large language models, image generation engines, and text-to-speech voice models. Prior to version 1.17.0, in src/endpoints/search.js, the hostname is checked against /^\\d+\\.\\d+\\.\\d+\\.\\d+$/. This only matches literal dotted-quad IPv4 (e.g. 127.0.0.1, 10.0.0.1). It does not catch: localhost (hostname, not dotted-quad), [::1] (IPv6 loopback), and DNS names resolving to internal addresses (e.g. localtest.me -> 127.0.0.1). A separate port check (urlObj.port !== '') limits exploitation to services on default ports (80/443), making this lower severity than a fully unrestricted SSRF. This issue has been patched in version 1.17.0.", "title": "nvd - https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-34526" }, { "category": "other", "text": "0.00025", "title": "EPSS" }, { "category": "other", "text": "3.9", "title": "NCSC Score" }, { "category": "other", "text": "The value of the most recent EPSS score, There is cwe data available from source Nvd", "title": "NCSC Score top decreasing factors" } ], "product_status": { "known_affected": [ "CSAFPID-5985091" ] }, "references": [ { "category": "external", "summary": "Source - github", "url": "https://api.github.com/advisories/GHSA-wm7j-m6jm-8797" }, { "category": "external", "summary": "Source - cveprojectv5", "url": "https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/34xxx/CVE-2026-34526.json" }, { "category": "external", "summary": "Source - nvd", "url": "https://services.nvd.nist.gov/rest/json/cves/2.0?cveId=CVE-2026-34526" }, { "category": "external", "summary": "Source - first", "url": "https://api.first.org/data/v1/epss?limit=10000&offset=0" }, { "category": "external", "summary": "Reference - cveprojectv5; github; nvd", "url": "https://github.com/SillyTavern/SillyTavern/security/advisories/GHSA-wm7j-m6jm-8797" }, { "category": "external", "summary": "Reference - github", "url": "https://github.com/advisories/GHSA-wm7j-m6jm-8797" }, { "category": "external", "summary": "Reference - cveprojectv5; nvd", "url": "https://github.com/SillyTavern/SillyTavern/releases/tag/1.17.0" } ], "scores": [ { "cvss_v3": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N", "baseScore": 5.0, "baseSeverity": "MEDIUM" }, "products": [ "CSAFPID-5985091" ] } ], "title": "CVE-2026-34526" } ] }