Critical
libssh2 - Out-of-Bounds Write via Unchecked packet_length in transport.c
libssh2 1.11.1, fixed in commit 97acf3d, 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.
Announced Source revision 1
Original source ↗CVE-2026-55200
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-55200
libssh2
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://github.com/libssh2/libssh2",
"vendor": "libssh2",
"product": "libssh2",
"versions": [
{
"status": "affected",
"version": "1.11.1",
"versionType": "semver"
},
{
"status": "affected",
"version": "1c3f1b7da588f2652260285529ec3c1f1125eb4e",
"lessThan": "97acf3dfda80c91c3a8c9f2372546301d4a1a7a8",
"versionType": "git"
}
],
"packageURL": "pkg:github/libssh2/libssh2",
"defaultStatus": "unaffected"
}
]- Related CVEs
- CVE-2026-55200
Source reference:
/cveMetadata/cveId
Publisher severity
critical
Source reference: /containers/cna/metrics
- Event
- #52255 · Revision 1
- Added to Heist Feed
- Publisher date