{"id":"CVE-2026-81535","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-81535","generatedAt":"2026-10-28T03:31:03.447Z","title":"In wolfSSH through 1.5.0 built with --enable-fwd, DoChannelOpen() in src/internal.c gates only direct-tcpip channel opens with the forwarding policy callback. forwarded-tcpip opens are admitted without an authorization check and are not capped in…","description":"In wolfSSH through 1.5.0 built with --enable-fwd, DoChannelOpen() in src/internal.c gates only direct-tcpip channel opens with the forwarding policy callback. forwarded-tcpip opens are admitted without an authorization check and are not capped in number, allowing a malicious SSH peer to make an endpoint allocate unbounded per-channel buffers for forwarding channels the application never authorized. A client also does not check a forwarded-tcpip open against the forwards it registered with a tcpip-forward request, as RFC 4254 section 7.2 requires, so a malicious server can open forwarding channels for addresses and ports the client never asked it to forward.","published":"2026-10-07T03:17:00.000Z","lastModified":"2026-10-13T17:36:16.000Z","status":"Analyzed","sourceIdentifier":"facts@wolfssl.com","cvss":{"version":"4.0","score":6.3,"severity":"MEDIUM","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M"},"cwe":["CWE-862","CWE-863"],"affected":["wolfssh/wolfssh"],"epss":{"score":0.00305,"percentile":0.23058,"date":"2026-10-26","history":[{"date":"2026-10-07","score":0.00276,"percentile":0.18371}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.30%). Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-07T03:17:00.000Z","detail":{"score":"6.3","severity":"MEDIUM","publishedAt":"2026-10-07T03:16:59.567Z"},"summary":"New CVE, medium severity (CVSS 6.3)."}],"references":[{"url":"https://github.com/wolfSSL/wolfssh/commit/616eb681e70759c30c3ba158f2b18d7bd954def8","tags":["Patch"],"source":"facts@wolfssl.com"},{"url":"https://github.com/wolfSSL/wolfssh/commit/79a7f299337a28aa561409688a268d0efe6e295c","tags":["Patch"],"source":"facts@wolfssl.com"},{"url":"https://github.com/wolfSSL/wolfssh/commit/e396a0a4b6b367f10270287446a4be0071742b5c","tags":["Patch"],"source":"facts@wolfssl.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-81535","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}