VDB
CVE-2026-55200
CVE-2026-55200
PUBLISHED
CVSS 9.2 CRITICAL
Reported by VulnCheck · Published June 17, 2026
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.
Risk Scores
CVSS 4.0
9.2
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
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| libssh2 | libssh2 | 0, 7acf3dfda80c91c3a8c9f2372546301d4a1a7a8 |
| alpine | rust | 0, 0, 0 |
| libssh2 | libssh2 | 0, 7acf3dfda80c91c3a8c9f2372546301d4a1a7a8, 1.11.1 |
| alpine | libssh2 | 0, 0, 0 |
Timeline
- Jun 17, 2026 CVE Published
- Jun 18, 2026 EPSS Score
- Jun 18, 2026 Coalition ESS Score
- Jun 19, 2026 Security Advisory
References
- Pull Request issue-tracking
- Patch Commit patch
- third-party-advisory
- https://github.com/bikini/exploitarium/tree/main/libssh2-cve-2026-55200-poc exploit
- https://web.archive.org/web/20260623211210/https://github.com/bikini/exploitarium/tree/main/libssh2-cve-2026-55200-poc exploit