Vulnerability Description
libssh2 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.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Libssh2 | Libssh2 | <= 1.11.1 |
Related Weaknesses (CWE)
References
- https://github.com/libssh2/libssh2/commit/97acf3dfda80c91c3a8c9f2372546301d4a1a7Patch
- https://github.com/libssh2/libssh2/pull/2052Patch
- https://www.vulncheck.com/advisories/libssh2-out-of-bounds-write-via-unchecked-pThird Party Advisory
- https://web.archive.org/web/20260623211210/https://github.com/bikini/exploitariuExploitThird Party Advisory
FAQ
What is CVE-2026-55200?
CVE-2026-55200 is a vulnerability with a CVSS score of 8.1 (HIGH). libssh2 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 s...
How severe is CVE-2026-55200?
CVE-2026-55200 has been rated HIGH with a CVSS base score of 8.1/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-55200?
Check the references section above for vendor advisories and patch information. Affected products include: Libssh2 Libssh2.