CVE-2026-59850: libssh. If data packets · Use After Free
Source GCVE Database
Not known to be exploited · CVSS 4.3 Medium · fixed in Red Hat Enterprise Linux 10 package updates : update Red Hat Enterprise Linux 10 when convenient.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 28% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 0.12.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:LExploitation evidence
Disclosed: evidence found.
CVE published 21 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
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
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Red Hat Enterprise Linux 10libssh | Affected– | Fixed in– |
| Red Hat Enterprise Linux 8libssh | Affected– | Fixed in– |
| Red Hat Enterprise Linux 8libssh | Affected– | Fixed in– |
| Red Hat Enterprise Linux 9libssh | Affected– | Fixed in– |
| Red Hat Enterprise Linux 9libssh | Affected– | Fixed in– |
| Red Hat Hardened Imageslibssh-main | Affected– | Fixed in– |
AI-suggested
Red Hat has released an official fix in libssh version 0.12.1-4.hum1 as part of their Hardened Images RPMs. Users should apply this update to remediate the vulnerability. Additionally, developers can manually verify that channels are not closed inside channel data callbacks as a mitigation measure. No other actions are currently required.
Description
A use-after-free vulnerability was found in libssh where data callbacks may be invoked after the associated data has been freed if data packets are processed after a channel is closed. This can lead to crashes or potential use-after-free conditions affecting availability.
References
- nvd.nist.gov/vuln/detail/CVE-2026-59850 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:42922 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-59850 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2498183 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:55855 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:62217 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:62218 (opens in a new tab)