Medium severity6.8OSV Advisory· Published Feb 18, 2025· Updated May 12, 2026
CVE-2025-26465
CVE-2025-26465
Description
A vulnerability was found in OpenSSH when the VerifyHostKeyDNS option is enabled. A machine-in-the-middle attack can be performed by a malicious machine impersonating a legit server. This issue occurs due to how OpenSSH mishandles error codes in specific conditions when verifying the host key. For an attack to be considered successful, the attacker needs to manage to exhaust the client's memory resource first, turning the attack complexity high.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected products
64ABOUT_TO_ADD_INET_ATON, AFTER_FREEBSD_PAM_MERGE, AFTER_KRB5_GSSAPI_MERGE, …+ 4 more
- (no CPE)range: ABOUT_TO_ADD_INET_ATON, AFTER_FREEBSD_PAM_MERGE, AFTER_KRB5_GSSAPI_MERGE, …
- cpe:2.3:a:openbsd:openssh:*:*:*:*:*:*:*:*range: >=6.9,<=9.8
- cpe:2.3:a:openbsd:openssh:6.8:p1:*:*:*:*:*:*
- cpe:2.3:a:openbsd:openssh:9.9:-:*:*:*:*:*:*
- cpe:2.3:a:openbsd:openssh:9.9:p1:*:*:*:*:*:*
- cpe:2.3:a:netapp:active_iq_unified_manager:-:*:*:*:*:vmware_vsphere:*:*
- cpe:2.3:a:redhat:openshift_container_platform:4.0:*:*:*:*:*:*:*
- cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*
- osv-coords52 versionspkg:rpm/almalinux/opensshpkg:rpm/almalinux/openssh-askpasspkg:rpm/almalinux/openssh-cavspkg:rpm/almalinux/openssh-clientspkg:rpm/almalinux/openssh-keycatpkg:rpm/almalinux/openssh-ldappkg:rpm/almalinux/openssh-serverpkg:rpm/almalinux/pam_ssh_agent_authpkg:rpm/opensuse/openssh-askpass-gnome&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/openssh&distro=openSUSE%20Leap%2015.6pkg:rpm/opensuse/openssh&distro=openSUSE%20Tumbleweedpkg:rpm/suse/openssh8.4&distro=SUSE%20Linux%20Enterprise%20Server%2012%20SP5-LTSSpkg:rpm/suse/openssh8.4&distro=SUSE%20Linux%20Enterprise%20Server%20LTSS%20Extended%20Security%2012%20SP5pkg:rpm/suse/openssh-askpass-gnome&distro=SUSE%20Enterprise%20Storage%207.1pkg:rpm/suse/openssh-askpass-gnome&distro=SUSE%20Linux%20Enterprise%20High%20Performance%20Computing%2015%20SP3-LTSSpkg:rpm/suse/openssh-askpass-gnome&distro=SUSE%20Linux%20Enterprise%20High%20Performance%20Computing%2015%20SP4-ESPOSpkg:rpm/suse/openssh-askpass-gnome&distro=SUSE%20Linux%20Enterprise%20High%20Performance%20Computing%2015%20SP4-LTSSpkg:rpm/suse/openssh-askpass-gnome&distro=SUSE%20Linux%20Enterprise%20High%20Performance%20Computing%2015%20SP5-ESPOSpkg:rpm/suse/openssh-askpass-gnome&distro=SUSE%20Linux%20Enterprise%20High%20Performance%20Computing%2015%20SP5-LTSSpkg:rpm/suse/openssh-askpass-gnome&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Desktop%20Applications%2015%20SP6pkg:rpm/suse/openssh-askpass-gnome&distro=SUSE%20Linux%20Enterprise%20Server%2012%20SP5-LTSSpkg:rpm/suse/openssh-askpass-gnome&distro=SUSE%20Linux%20Enterprise%20Server%2015%20SP3-LTSSpkg:rpm/suse/openssh-askpass-gnome&distro=SUSE%20Linux%20Enterprise%20Server%2015%20SP4-LTSSpkg:rpm/suse/openssh-askpass-gnome&distro=SUSE%20Linux%20Enterprise%20Server%2015%20SP5-LTSSpkg:rpm/suse/openssh-askpass-gnome&distro=SUSE%20Linux%20Enterprise%20Server%20for%20SAP%20Applications%2015%20SP3pkg:rpm/suse/openssh-askpass-gnome&distro=SUSE%20Linux%20Enterprise%20Server%20for%20SAP%20Applications%2015%20SP4pkg:rpm/suse/openssh-askpass-gnome&distro=SUSE%20Linux%20Enterprise%20Server%20for%20SAP%20Applications%2015%20SP5pkg:rpm/suse/openssh-askpass-gnome&distro=SUSE%20Linux%20Enterprise%20Server%20LTSS%20Extended%20Security%2012%20SP5pkg:rpm/suse/openssh&distro=SUSE%20Enterprise%20Storage%207.1pkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20High%20Performance%20Computing%2015%20SP3-LTSSpkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20High%20Performance%20Computing%2015%20SP4-ESPOSpkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20High%20Performance%20Computing%2015%20SP4-LTSSpkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20High%20Performance%20Computing%2015%20SP5-ESPOSpkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20High%20Performance%20Computing%2015%20SP5-LTSSpkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20Micro%205.1pkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20Micro%205.2pkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20Micro%205.3pkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20Micro%205.4pkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20Micro%205.5pkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20Module%20for%20Basesystem%2015%20SP6pkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20Server%2012%20SP5-LTSSpkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20Server%2015%20SP3-LTSSpkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20Server%2015%20SP4-LTSSpkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20Server%2015%20SP5-LTSSpkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20Server%20for%20SAP%20Applications%2015%20SP3pkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20Server%20for%20SAP%20Applications%2015%20SP4pkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20Server%20for%20SAP%20Applications%2015%20SP5pkg:rpm/suse/openssh&distro=SUSE%20Linux%20Enterprise%20Server%20LTSS%20Extended%20Security%2012%20SP5pkg:rpm/suse/openssh&distro=SUSE%20Linux%20Micro%206.0pkg:rpm/suse/openssh&distro=SUSE%20Linux%20Micro%206.1pkg:rpm/suse/openssh&distro=SUSE%20Manager%20Proxy%204.3pkg:rpm/suse/openssh&distro=SUSE%20Manager%20Server%204.3
< 8.0p1-26.el8_10+ 51 more
- (no CPE)range: < 8.0p1-26.el8_10
- (no CPE)range: < 8.0p1-26.el8_10
- (no CPE)range: < 8.0p1-26.el8_10
- (no CPE)range: < 8.0p1-26.el8_10
- (no CPE)range: < 8.0p1-26.el8_10
- (no CPE)range: < 8.0p1-26.el8_10
- (no CPE)range: < 8.0p1-26.el8_10
- (no CPE)range: < 0.10.3-7.26.el8_10
- (no CPE)range: < 9.6p1-150600.6.15.1
- (no CPE)range: < 9.6p1-150600.6.15.2
- (no CPE)range: < 9.9p2-1.1
- (no CPE)range: < 8.4p1-8.16.1
- (no CPE)range: < 8.4p1-8.16.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 9.6p1-150600.6.15.1
- (no CPE)range: < 7.2p2-81.26.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 7.2p2-81.26.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 9.6p1-150600.6.15.2
- (no CPE)range: < 7.2p2-81.26.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 7.2p2-81.26.1
- (no CPE)range: < 9.6p1-3.1
- (no CPE)range: < 9.6p1-slfo.1.1_2.1
- (no CPE)range: < 8.4p1-150300.3.42.1
- (no CPE)range: < 8.4p1-150300.3.42.1
Patches
Vulnerability mechanics
References
26- ftp.openbsd.org/pub/OpenBSD/patches/7.6/common/008_ssh.patch.signvdPatch
- access.redhat.com/security/cve/CVE-2025-26465nvdThird Party Advisory
- blog.qualys.com/vulnerabilities-threat-research/2025/02/18/qualys-tru-discovers-two-vulnerabilities-in-openssh-cve-2025-26465-cve-2025-26466nvdThird Party Advisory
- bugzilla.redhat.com/show_bug.cginvdIssue TrackingThird Party Advisory
- lists.debian.org/debian-lts-announce/2025/02/msg00020.htmlnvdThird Party Advisory
- lists.mindrot.org/pipermail/openssh-unix-announce/2025-February/000161.htmlnvdThird Party Advisory
- seclists.org/oss-sec/2025/q1/144nvdMailing ListThird Party Advisory
- security-tracker.debian.org/tracker/CVE-2025-26465nvdThird Party Advisory
- security.netapp.com/advisory/ntap-20250228-0003/nvdThird Party Advisory
- ubuntu.com/security/CVE-2025-26465nvdThird Party Advisory
- www.openwall.com/lists/oss-security/2025/02/18/1nvdMailing ListThird Party Advisory
- www.openwall.com/lists/oss-security/2025/02/18/4nvdMailing ListThird Party Advisory
- www.vicarius.io/vsociety/posts/cve-2025-26465-detect-vulnerable-opensshnvdThird Party Advisory
- www.vicarius.io/vsociety/posts/cve-2025-26465-mitigate-vulnerable-opensshnvdMitigationThird Party Advisory
- bugzilla.suse.com/show_bug.cginvdIssue Tracking
- www.openssh.com/releasenotes.htmlnvdRelease Notes
- www.theregister.com/2025/02/18/openssh_vulnerabilities_mitm_dos/nvdPress/Media Coverage
- seclists.org/fulldisclosure/2025/Feb/18nvd
- seclists.org/fulldisclosure/2025/May/7nvd
- seclists.org/fulldisclosure/2025/May/8nvd
- access.redhat.com/errata/RHSA-2025:16823nvd
- access.redhat.com/errata/RHSA-2025:3837nvd
- access.redhat.com/errata/RHSA-2025:6993nvd
- access.redhat.com/errata/RHSA-2025:8385nvd
- access.redhat.com/solutions/7109879nvd
- cert-portal.siemens.com/productcert/html/ssa-082556.htmlnvd
News mentions
2- Only a Handful of CVEs Mattered for Supply Chain in 2025GovInfoSecurity · May 19, 2026
- Risky Business #780 -- ASD torched Zservers data while admins were drunkRisky Business · Feb 19, 2025