CVE-2026-59845 (GCVE-0-2026-59845)

Vulnerability from cvelistv5 – Published: 2026-07-21 11:26 – Updated: 2026-07-22 19:07
VLAI
Title
Libssh: libssh: denial of service via unchecked proxycommand fork() failure
Summary
A flaw was found in libssh. When ProxyCommand is used, an unchecked fork() failure can be stored as process ID -1; during cleanup, signals may then be sent across the caller's accessible process tree, leading to local denial of service.
Severity
5.3 (Medium)
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:N/I:N/A:H
Assigner
References
URL Tags
https://access.redhat.com/errata/RHSA-2026:42922 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-59845 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2498178 issue-trackingx_refsource_REDHAT
Impacted products
Vendor Product Version
Red Hat Red Hat Hardened Images Unaffected: 0.12.1-4.hum1 , < * (rpm)
    cpe:/a:redhat:hummingbird:1
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Red Hat Red Hat Enterprise Linux 10     cpe:/o:redhat:enterprise_linux:10
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Red Hat Red Hat Enterprise Linux 8     cpe:/o:redhat:enterprise_linux:8
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Red Hat Red Hat Enterprise Linux 9     cpe:/o:redhat:enterprise_linux:9
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Date Public
2026-07-21 11:23
Credits
Red Hat would like to thank Halil Oktay (oblivionsage) for reporting this issue.
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.