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TI-2026-42780 Aliases CVE-2026-59998GHSA-3j2g-cqmq-cjw9

sshd in OpenSSH before 10.4 has an undocumented security-relevant behavior…

Priority LOW 28CWE-573Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
Low · Low · None
Fix status
Partial Red Hat: 9 fixed, 5 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat.

Summary

sshd in OpenSSH before 10.4 has an undocumented security-relevant behavior: GSSAPIStrictAcceptorCheck has no value if the server is in Windows Active Directory.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0018 7th percentileScored 2026-11-07
Fix Partial OpenSSH (OpenBSD): 10.4Red Hat: 6 advisoriesRed Hat: 9 fixed, 5 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
OpenBSDOpenSSHbefore 10.410.4Patch availableCNA
  • OpenSSH VendorOpenBSD Affected before 10.4 Fixed in 10.4 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:openbsd:openssh:*:*:*:*:*:*:*:*before 10.4VulnerableOpenBSD
  • cpe:2.3:a:openbsd:openssh:*:*:*:*:*:*:*:* Versions before 10.4 Vulnerable ·OpenBSD

Remediation

  • Fix · CNA OpenSSH (OpenBSD) Fixed in 10.4

Red Hat 6 advisories

  • RHSA-2026:94802 Released 2026-11-04 · Red Hat rating Critical
    A Subscription Management tool for finding and reporting Red Hat product usage
    • Red Hat Discovery 2 registry.redhat.io/discovery/discovery-server-rhel9, registry.redhat.io/discovery/discovery-ui-rhel9
  • RHSA-2026:89907 Released 2026-10-26 · Red Hat rating Critical
    Red Hat Update Infrastructure 5.3 security update
    • Red Hat Update Infrastructure 5 registry.redhat.io/rhui5/cds-kubernetes-rhel9, registry.redhat.io/rhui5/cds-rhel9, registry.redhat.io/rhui5/haproxy-rhel9 +2
  • RHSA-2026:88211 Released 2026-10-22 · Red Hat rating Moderate
    openssh security update
    • Red Hat Enterprise Linux AppStream (v. 8) openssh-askpass-8.0p1-34.el8_10
    • Red Hat Enterprise Linux BaseOS (v. 8) openssh-8.0p1-34.el8_10, openssh-cavs-8.0p1-34.el8_10, openssh-clients-8.0p1-34.el8_10 +4
Show 3 more Red Hat advisories
  • RHSA-2026:85958 Released 2026-10-20 · Red Hat rating Moderate
    openssh security update
    • Red Hat Enterprise Linux AppStream (v. 9) openssh-askpass-9.9p1-13.el9_8, pam_ssh_agent_auth-0.10.4-8.13.el9_8
    • Red Hat Enterprise Linux BaseOS (v. 9) openssh-9.9p1-13.el9_8, openssh-clients-9.9p1-13.el9_8, openssh-keycat-9.9p1-13.el9_8 +1
  • RHSA-2026:85847 Released 2026-10-20 · Red Hat rating Moderate
    openssh security update
    • Red Hat Enterprise Linux AppStream (v. 10) openssh-askpass-9.9p1-29.el10_2, openssh-keysign-9.9p1-29.el10_2
    • Red Hat Enterprise Linux BaseOS (v. 10) openssh-9.9p1-29.el10_2, openssh-clients-9.9p1-29.el10_2, openssh-keycat-9.9p1-29.el10_2 +1
  • RHSA-2026:37382 Released 2026-07-09 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images openssh-10.4p1-1.hum1@aarch64, openssh-10.4p1-1.hum1@src, openssh-10.4p1-1.hum1@x86_64 +12

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    OpenBSD OpenSSH 10.4

    8 records Highest priority Priority MEDIUM 1 MEDIUM, 7 LOW

    Other records, highest priority first

    • TI-2026-42784 Use after free in OpenBSD OpenSSHPriority MEDIUM 42
    • TI-2026-42783 sshd in OpenSSH before 10.4 does not always honor the minimum authentication delay.Priority LOW 35
    • TI-2026-42782 Resource allocation without limits in OpenBSD OpenSSHPriority LOW 34
    Show all 8 records →

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 6AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 7AffectedNo fix yet: Fix deferred
Red Hat OpenShift AI (RHOAI)Affected—
Red Hat OpenShift Container Platform 4AffectedNo fix yet: Fix deferred
Red Hat OpenShift Container Platform 5AffectedNo fix yet: Fix deferred
Red Hat Discovery 2Fixed RHSA-2026:94802
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:85847
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2026:88211
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:85958
Red Hat Enterprise Linux BaseOS (v. 10)Fixed RHSA-2026:85847
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2026:88211
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2026:85958
Red Hat Hardened ImagesFixed RHSA-2026:37382
Red Hat Update Infrastructure 5Fixed RHSA-2026:89907
Not affected: 2 products
  • Red Hat Discovery 2
  • Red Hat Update Infrastructure 5

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-59998
  2. 2026-10-03 Alias added: GHSA-3j2g-cqmq-cjw9
  3. 2026-10-20 Fix available: RHSA-2026:85847 · Red Hat
  4. 2026-10-20 Fix available: Red Hat Enterprise Linux AppStream (v. 10), Red Hat Enterprise Linux BaseOS (v. 10) · Red Hat
  5. 2026-10-21 Fix available: RHSA-2026:85958 · Red Hat
  6. 2026-10-21 Fix available: Red Hat Enterprise Linux AppStream (v. 9), Red Hat Enterprise Linux BaseOS (v. 9) · Red Hat
  7. 2026-10-23 Fix available: RHSA-2026:88211 · Red Hat
  8. 2026-10-23 Fix available: Red Hat Enterprise Linux AppStream (v. 8), Red Hat Enterprise Linux BaseOS (v. 8) · Red Hat
  9. 2026-10-30 Fix available: RHSA-2026:89907 · Red Hat
  10. 2026-10-30 Fix available: Red Hat Update Infrastructure 5 · Red Hat
  11. 2026-11-04 Fix available: RHSA-2026:94802 · Red Hat
  12. 2026-11-04 Fix available: Red Hat Discovery 2 · Red Hat
  13. 2026-11-06 Affected versions changed · Red Hat

References

Other 3

  • TI-2023-19792 The PKCS#11 feature in ssh-agent in OpenSSH before 9.3p2 has an insufficiently… CVSS 3.1CRITICAL 9.8
  • TI-2024-05929 Openssh: regresshion - race condition in ssh allows rce/dos CVSS 3.1HIGH 8.1
  • TI-2023-10601 OpenSSH server (sshd) 9.1 introduced a double-free vulnerability during… CVSS 3.1MEDIUM 6.5
  • TI-2018-11033 OpenSSH through 7.7 is prone to a user enumeration vulnerability due to not delaying… CVSS 3.1MEDIUM 5.9
  • TI-2016-08105 Untrusted search path vulnerability in ssh-agent.c in ssh-agent in OpenSSH before 7.4… CVSS 3.1HIGH 7.3
  • TI-2023-28040 In ssh in OpenSSH before 9.6, OS command injection might occur if a user name or host… CVSS 3.1MEDIUM 6.5
See all 145 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences