CVE-2026-55200
critical · 9.2libssh2 through 1.11.1, fixed in commit 7acf3df contains an out-of-bounds write vulnerability in ssh2_transport_read() that fails to enforce upper bounds on packet_length field. Remote attackers can send crafted SSH packets with excessively large packet_length values to corrupt heap memory and achieve remote code execution.
9.2
CVSS
4.0%
EPSS (exploit prob.)
90th
EPSS percentile
2026-06-17
Published
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/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
Weaknesses
CWE-680
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| libssh2 | libssh2 | 1.11.1 |
Check a specific version with /api/v1/cve/match.
References
- https://github.com/libssh2/libssh2/commit/97acf3dfda80c91c3a8c9f2372546301d4a1a7a8
- https://github.com/libssh2/libssh2/pull/2052
- https://www.vulncheck.com/advisories/libssh2-out-of-bounds-write-via-unchecked-packet-length-in-transport-c
- https://web.archive.org/web/20260623211210/https://github.com/bikini/exploitarium/tree/main/libssh2-cve-2026-55200-poc
Query this programmatically:
curl https://evil-db.io/api/v1/cve/CVE-2026-55200