CVE-2026-81535
In wolfSSH through 1.5.0 built with --enable-fwd, DoChannelOpen() in src/internal.c gates only direct-tcpip c…
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.
- Vendor
- wolfssh
- Product
- wolfssh
- CVSS 3.1
- 9.1 (critical), scored by NVD (primary)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- CVSS 4.0
- 6.3 (medium), scored by facts@wolfssl.comCVSS: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/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- Published
- 2026-10-07
- NVD modified
- 2026-10-13
- NVD status
- Analyzed
Not in the CISA KEV catalogue at the last update.
EPSS
0.27% chance of exploitation in the next 30 days (percentile 17th)
FIRST EPSS, updated 17 Oct 2026. About EPSS
CVSS is severity, EPSS is likelihood, KEV means already exploited. EPSS is a statistical probability, not a certainty: a low score does not make a bug safe, and a high one does not prove it is being exploited.
ThreatWire coverage
References
- github.com (Patch)
- github.com (Patch)
- github.com (Patch)
Data last updated 18 Oct 2026. Sources: NVD API 2.0, FIRST EPSS. Links: NVD, CISA KEV. Metadata only. ThreatWire does not host exploit code.