synced 13 MIN AGO
01 Record

CVE-2026-35388

OpenSSH before 10.3 omits connection multiplexing confirmation for proxy-mode multiplexing sessions.

LowPUBLISHEDCNA: mitre
CNA base score2.5 CVSS v3.xCVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N
View raw JSON

02 Description

OpenSSH before 10.3 omits connection multiplexing confirmation for proxy-mode multiplexing sessions.

03 Exploitation and scoring

Exploitation
Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.
SSVC decision
  • ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
  • AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
  • Technical ImpactpartialSuccessful exploitation gives limited control of the vulnerable component.
CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.
EPSS probability
0.13% probability of exploitation activity in the next 30 days.
EPSS percentile
Equal to or higher than the score of 2.5% of scored records. A rank, not a probability.
NVD base score
2.5 (CVSS v3.x), scored by the NVD independently of the CNA.
NVD CVSS vector
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N
NVD analysis status
Analyzed. NVD last modified this record on 2026-07-24.
Red Hat severity
Low. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

04 Metadata

Published
2026-04-02 16:57Z6 MO AGO
Last updated
2026-04-02 18:16Z6 MO AGO
Reserved
2026-04-02
Assigning CNA
mitre
Record state
PUBLISHED
Severity
Low (CVSS 2.5)
CNA CVSS vector
CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N
Weaknesses
  • CWE-420Unprotected Alternate ChannelBase
  • CWE-306Missing Authentication for Critical FunctionBase
Data version
5.2
Document digest
817dfd55dfcfef2fffcf9bb37436caac2e2b17e3b2b01529527ba97444d371d0

05 Affected products

VendorProductVersionsPlatforms
OpenBSDOpenSSH0 to < 10.3—

06 References

07 Fixed in

AlmaLinux 8

  • openssh
    Fixed in 8.0p1-29.el8_10
  • openssh-askpass
    Fixed in 8.0p1-29.el8_10
  • openssh-cavs
    Fixed in 8.0p1-29.el8_10
  • openssh-clients
    Fixed in 8.0p1-29.el8_10
  • openssh-keycat
    Fixed in 8.0p1-29.el8_10
  • openssh-ldap
    Fixed in 8.0p1-29.el8_10
  • openssh-server
    Fixed in 8.0p1-29.el8_10
  • pam_ssh_agent_auth
    Fixed in 0.10.3-7.29.el8_10

Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

AlmaLinux 9

  • openssh
    Fixed

    A version is affected if any line below covers it.

    • Affected before 8.7p1-49.el9_7.alma.1
    • Affected before 9.9p1-7.el9_8.alma.1
  • openssh-askpass
    Fixed

    A version is affected if any line below covers it.

    • Affected before 8.7p1-49.el9_7.alma.1
    • Affected before 9.9p1-7.el9_8.alma.1
  • openssh-clients
    Fixed

    A version is affected if any line below covers it.

    • Affected before 8.7p1-49.el9_7.alma.1
    • Affected before 9.9p1-7.el9_8.alma.1
  • openssh-keycat
    Fixed

    A version is affected if any line below covers it.

    • Affected before 8.7p1-49.el9_7.alma.1
    • Affected before 9.9p1-7.el9_8.alma.1
  • openssh-server
    Fixed

    A version is affected if any line below covers it.

    • Affected before 8.7p1-49.el9_7.alma.1
    • Affected before 9.9p1-7.el9_8.alma.1
  • pam_ssh_agent_auth
    Fixed

    A version is affected if any line below covers it.

    • Affected before 0.10.4-5.49.el9_7.alma.1
    • Affected before 0.10.4-7.7.el9_8.alma.1

Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

AlmaLinux 10

  • openssh
    Fixed

    A version is affected if any line below covers it.

    • Affected before 9.9p1-14.el10_1.alma.1
    • Affected before 9.9p1-23.el10_2.alma.1
  • openssh-askpass
    Fixed

    A version is affected if any line below covers it.

    • Affected before 9.9p1-14.el10_1.alma.1
    • Affected before 9.9p1-23.el10_2.alma.1
  • openssh-clients
    Fixed

    A version is affected if any line below covers it.

    • Affected before 9.9p1-14.el10_1.alma.1
    • Affected before 9.9p1-23.el10_2.alma.1
  • openssh-keycat
    Fixed

    A version is affected if any line below covers it.

    • Affected before 9.9p1-14.el10_1.alma.1
    • Affected before 9.9p1-23.el10_2.alma.1
  • openssh-keysign
    Fixed

    A version is affected if any line below covers it.

    • Affected before 9.9p1-14.el10_1.alma.1
    • Affected before 9.9p1-23.el10_2.alma.1
  • openssh-server
    Fixed

    A version is affected if any line below covers it.

    • Affected before 9.9p1-14.el10_1.alma.1
    • Affected before 9.9p1-23.el10_2.alma.1

Source: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

CloudLinux 8

  • openssh
    Fixed in 8.0p1-29.el8_10
  • openssh-askpass
    Fixed in 8.0p1-29.el8_10
  • openssh-cavs
    Fixed in 8.0p1-29.el8_10
  • openssh-clients
    Fixed in 8.0p1-29.el8_10
  • openssh-keycat
    Fixed in 8.0p1-29.el8_10
  • openssh-ldap
    Fixed in 8.0p1-29.el8_10
  • openssh-server
    Fixed in 8.0p1-29.el8_10
  • pam_ssh_agent_auth
    Fixed in 0.10.3-7.29.el8_10

Derived from AlmaLinux 8. Partial coverage: only packages taken from AlmaLinux 8 are listed.

Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

CloudLinux 9

  • openssh
    Fixed

    A version is affected if any line below covers it.

    • Affected before 8.7p1-49.el9_7.alma.1
    • Affected before 9.9p1-7.el9_8.alma.1
  • openssh-askpass
    Fixed

    A version is affected if any line below covers it.

    • Affected before 8.7p1-49.el9_7.alma.1
    • Affected before 9.9p1-7.el9_8.alma.1
  • openssh-clients
    Fixed

    A version is affected if any line below covers it.

    • Affected before 8.7p1-49.el9_7.alma.1
    • Affected before 9.9p1-7.el9_8.alma.1
  • openssh-keycat
    Fixed

    A version is affected if any line below covers it.

    • Affected before 8.7p1-49.el9_7.alma.1
    • Affected before 9.9p1-7.el9_8.alma.1
  • openssh-server
    Fixed

    A version is affected if any line below covers it.

    • Affected before 8.7p1-49.el9_7.alma.1
    • Affected before 9.9p1-7.el9_8.alma.1
  • pam_ssh_agent_auth
    Fixed

    A version is affected if any line below covers it.

    • Affected before 0.10.4-5.49.el9_7.alma.1
    • Affected before 0.10.4-7.7.el9_8.alma.1

Derived from AlmaLinux 9. Partial coverage: only packages taken from AlmaLinux 9 are listed.

Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

CloudLinux 10

  • openssh
    Fixed

    A version is affected if any line below covers it.

    • Affected before 9.9p1-14.el10_1.alma.1
    • Affected before 9.9p1-23.el10_2.alma.1
  • openssh-askpass
    Fixed

    A version is affected if any line below covers it.

    • Affected before 9.9p1-14.el10_1.alma.1
    • Affected before 9.9p1-23.el10_2.alma.1
  • openssh-clients
    Fixed

    A version is affected if any line below covers it.

    • Affected before 9.9p1-14.el10_1.alma.1
    • Affected before 9.9p1-23.el10_2.alma.1
  • openssh-keycat
    Fixed

    A version is affected if any line below covers it.

    • Affected before 9.9p1-14.el10_1.alma.1
    • Affected before 9.9p1-23.el10_2.alma.1
  • openssh-keysign
    Fixed

    A version is affected if any line below covers it.

    • Affected before 9.9p1-14.el10_1.alma.1
    • Affected before 9.9p1-23.el10_2.alma.1
  • openssh-server
    Fixed

    A version is affected if any line below covers it.

    • Affected before 9.9p1-14.el10_1.alma.1
    • Affected before 9.9p1-23.el10_2.alma.1

Derived from AlmaLinux 10. Partial coverage: only packages taken from AlmaLinux 10 are listed.

Source: CloudLinux errata, CloudLinux Inc. Derived from: AlmaLinux, AlmaLinux OS. Copyright (c) 2023 AlmaLinux OS. Licensed under MIT License. Received through OSV.dev. Reformatted by exploit.cc.

Debian 12

  • openssh
    Fixed in 1:9.2p1-2+deb12u10

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Debian 13

  • openssh
    Fixed in 1:10.0p1-7+deb13u3

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Debian 14

  • openssh
    Fixed in 1:10.3p1-1

Source: Debian Security Tracker, the Debian security team. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 18.04 LTS

  • openssh-ssh1
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 20.04 LTS

  • openssh-ssh1
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 22.04 LTS

  • openssh
    Fixed in 1:8.9p1-3ubuntu0.15
  • openssh-ssh1
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 24.04 LTS

  • openssh
    Fixed in 1:9.6p1-3ubuntu13.16
  • openssh-ssh1
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 25.10

  • openssh
    Fixed in 1:10.0p1-5ubuntu5.4
  • openssh-ssh1
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 26.04 LTS

  • openssh
    Fixed in 1:10.2p1-2ubuntu3.2
  • openssh-ssh1
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu 26.10

  • openssh-ssh1
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro 14.04 LTS

  • openssh
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro 16.04 LTS

  • openssh
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro 18.04 LTS

  • openssh
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro 20.04 LTS

  • openssh
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro FIPS-preview 22.04 LTS

  • openssh
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro FIPS-updates 16.04 LTS

  • openssh
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro FIPS-updates 18.04 LTS

  • openssh
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro FIPS-updates 20.04 LTS

  • openssh
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro FIPS-updates 22.04 LTS

  • openssh
    Fixed in 1:8.9p1-3ubuntu0.15+Fips1
    Available with Ubuntu Pro: https://ubuntu.com/pro

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro FIPS-updates 24.04 LTS

  • openssh
    Fixed in 1:9.6p1-3ubuntu13.16+Fips1
    Available with Ubuntu Pro: https://ubuntu.com/pro

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro FIPS 16.04 LTS

  • openssh
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro FIPS 18.04 LTS

  • openssh
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

Ubuntu Pro FIPS 20.04 LTS

  • openssh
    No fix yet

Source: Ubuntu, Canonical Ltd. Licensed under CC BY-SA 4.0. Received through OSV.dev. Reformatted by exploit.cc.

A release or ecosystem missing from this list has no record here. It may be unaffected or not covered by the source. Source notices and licences.