libssh2 1.11.1, fixed
Affects libssh2Source GCVE Database
Not known to be exploited · CVSS 9.2 Critical · fixed in 1.11.1-1ubuntu0.25.10.2 : patch libssh2 as a priority.
Data as of 28 Oct 2026, 22:28 UTC
- Patch
- Available – fixed in 1.11.1-1ubuntu0.25.10.2, 1.11.1-1ubuntu0.26.04.2
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NExploitation evidence
t = 0 is the CVE’s publication on cve.org
Disclosed: evidence found.
CVE published 17 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: evidence found.
CISA SSVC: proof of concept public
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
Timeline
CVE ID reserved
by VulnCheck
, 27 hours before disclosure
CVE published
on cve.org
, t = 0
CISA SSVC assessment
proof of concept public
, the same day as disclosure
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CISA SSVC, the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade the Ubuntu libssh2 to 1.11.1-1ubuntu0.25.10.2 (package) or 1.11.1-1ubuntu0.26.04.2 (package).
Patches and advisories
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlibssh2pkg:deb/ubuntu/libssh2?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 25.10libssh2pkg:deb/ubuntu/libssh2?arch=source&distro=questingOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
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.