CVE-2026-59845: libssh · CWE-390
Source GCVE Database
Not known to be exploited · CVSS 5.3 Medium.
Data as of 30 Oct 2026, 06:59 UTC
- EPSS
- 0.1% chance of exploitation in 30 days – higher than 1% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:N/I:N/A:HExploitation 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 advises avoiding the use of the ProxyCommand feature in libssh client configurations to mitigate this issue. This prevents the vulnerable code path from being exercised and eliminates the risk of local denial of service caused by unchecked fork() failures. A fixed package version (libssh-0.12.1-4.hum1) is available in Red Hat Hardened Images RPMs. Users should apply this update where applicable.
Description
A vulnerability in libssh affects the ProxyCommand feature, where an unchecked fork() failure can be recorded as process ID -1. During cleanup, this can cause signals to be sent across the caller's accessible process tree, resulting in a local denial of service. This issue impacts environments using ProxyCommand in libssh client configurations.
References
- nvd.nist.gov/vuln/detail/CVE-2026-59845 (opens in a new tab)
- access.redhat.com/errata/RHSA-2026:42922 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2026-59845 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2498178 (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)