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TI-2026-69089 Aliases CVE-2026-106582GHSA-9xxf-58mh-q784

Covert channel in OpenSSH sshd and ssh via LZ77 compression

Priority LOW 17CWE-514Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
Low · None · None
Fix status
Partial Red Hat: 1 fixed, 8 without a fix

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

Summary

OpenSSH before 10.6 lets sshd and ssh use an LZ77 dictionary coder that the arXiv 2609.07709 "Crossing the Streams" findings contraindicate, which creates a covert channel (CWE-514). A remote attacker with no privileges and no user interaction can leak limited information, but the attack has high complexity.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

Description from the CNA

In sshd and ssh in OpenSSH before 10.6, an LZ77 dictionary coder can be used even though this is contraindicated by the arXiv 2609.07709 "Crossing the Streams" findings.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00183 7th percentileScored 2026-11-07
Fix Partial OpenSSH (OpenBSD): 10.6Red Hat: 1 advisoryRed Hat: 1 fixed, 8 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 10.610.6Patch availableCNA
  • OpenSSH VendorOpenBSD Affected before 10.6 Fixed in 10.6 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:openbsd:openssh:*:*:*:*:*:*:*:*before 10.6VulnerableOpenBSD
  • cpe:2.3:a:openbsd:openssh:*:*:*:*:*:*:*:* Versions before 10.6 Vulnerable ·OpenBSD

Remediation

OpenSSH is fixed in version 10.6. Red Hat fixes Red Hat Hardened Images in RHSA-2026:82247, released 2026-10-13. Red Hat lists Red Hat Enterprise Linux 6, 7, 8, 9 and 10, Red Hat OpenShift AI and Red Hat OpenShift Container Platform 4 and 5 as affected without a fix, with no fix plan available for Red Hat Enterprise Linux and OpenShift Container Platform and no plan given for OpenShift AI.

Written with Claude Haiku 5.5 from the sources below · 2026-11-06

  • Fix · CNA OpenSSH (OpenBSD) Fixed in 10.6

Red Hat 1 advisory

  • RHSA-2026:82247 Released 2026-10-13 · Red Hat rating Moderate
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images openssh-10.5p1-1.2.hum1@aarch64, openssh-10.5p1-1.2.hum1@s390x, openssh-10.5p1-1.2.hum1@src +19

Fixed in the same release

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

  • Release ·

    OpenBSD OpenSSH 10.6

    9 records Highest priority Priority LOW 9 LOW

    Other records, highest priority first

    • TI-2026-69092 Missing packet length check in OpenSSH sshd and ssh decompressionPriority LOW 34
    • TI-2026-69090 Injection via command-line usernames in OpenSSH ssh clientPriority LOW 33
    • TI-2026-69088 GSSAPI authentication state persists across attempts in OpenSSH sshdPriority LOW 32
    Show all 9 records →

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet
Red Hat Enterprise Linux 6AffectedNo fix yet
Red Hat Enterprise Linux 7AffectedNo fix yet
Red Hat Enterprise Linux 8AffectedNo fix yet
Red Hat Enterprise Linux 9AffectedNo fix yet
Red Hat OpenShift AI (RHOAI)Affected—
Red Hat OpenShift Container Platform 4AffectedNo fix yet
Red Hat OpenShift Container Platform 5AffectedNo fix yet
Red Hat Hardened ImagesFixed RHSA-2026:82247
Not affected: 1 product
  • Red Hat Hardened Images

Timeline

  1. 2026-10-07 Threatist record created from CVE-2026-106582
  2. 2026-10-07 Alias added: GHSA-9xxf-58mh-q784
  3. 2026-10-07 CISA SSVC decision points changed
  4. 2026-10-20 Fix available: RHSA-2026:82247 · Red Hat
  5. 2026-10-20 Fix available: Red Hat Hardened Images · Red Hat
  6. 2026-10-20 CVSS score added · Red Hat
  7. 2026-10-30 Affected versions changed · Red Hat
  8. 2026-11-06 Affected versions changed · Red Hat

References

Advisory 1

Other 1

  • 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