HighFix available
libssh2, rust — security advisory
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.
- Products
- libssh2, rust
- Affected versions
- Not specified
- Fixed versions
- 1.11.1-r2, 1.11.1-r3, 1.96.1-r0
- CVEs
- CVE-2026-55200
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 1 Nov 2026, 02:32 UTC · Revision 1
Source evidence
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.
osv:ALPINE-CVE-2026-55200
libssh2
Fixed versions: 1.11.1-r2
libssh2
Fixed versions: 1.11.1-r2
libssh2
Fixed versions: 1.11.1-r3
libssh2
Fixed versions: 1.11.1-r3
rust
Fixed versions: 1.96.1-r0
Complete source record
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"method": "structured",
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"summary": "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.",
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"modified": "2026-10-23T18:30:03.516227683Z",
"provider": "osv",
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"source_id": "core-osv",
"document_id": 424591,
"published_at": "2026-06-17T20:17:28.667+00:00"
}