{"id":"CVE-2025-26466","details":"A flaw was found in the OpenSSH package. For each ping packet the SSH server receives, a pong packet is allocated in a memory buffer and stored in a queue of packages. It is only freed when the server/client key exchange has finished. A malicious client may keep sending such packages, leading to an uncontrolled increase in memory consumption on the server side. Consequently, the server may become unavailable, resulting in a denial of service attack.","modified":"2026-04-10T05:23:32.688964Z","published":"2025-02-28T22:15:40.080Z","related":["SUSE-SU-2025:0585-1","SUSE-SU-2025:20160-1","SUSE-SU-2025:20226-1","openSUSE-SU-2025:14820-1"],"references":[{"type":"WEB","url":"http://seclists.org/fulldisclosure/2025/May/7"},{"type":"WEB","url":"https://www.vicarius.io/vsociety/posts/cve-2025-26466-mitigation-script-memory-consumption-vulnerability-in-openssh"},{"type":"WEB","url":"http://seclists.org/fulldisclosure/2025/Feb/18"},{"type":"WEB","url":"http://seclists.org/fulldisclosure/2025/May/8"},{"type":"WEB","url":"https://seclists.org/oss-sec/2025/q1/144"},{"type":"WEB","url":"https://www.vicarius.io/vsociety/posts/cve-2025-26466-detection-script-memory-consumption-vulnerability-in-openssh"},{"type":"ADVISORY","url":"https://security.netapp.com/advisory/ntap-20250228-0002/"},{"type":"ADVISORY","url":"https://ubuntu.com/security/CVE-2025-26466"},{"type":"ADVISORY","url":"https://www.openwall.com/lists/oss-security/2025/02/18/1"},{"type":"ADVISORY","url":"https://access.redhat.com/security/cve/CVE-2025-26466"},{"type":"ADVISORY","url":"https://security-tracker.debian.org/tracker/CVE-2025-26466"},{"type":"ADVISORY","url":"https://www.openwall.com/lists/oss-security/2025/02/18/4"},{"type":"ADVISORY","url":"https://www.qualys.com/2025/02/18/openssh-mitm-dos.txt"},{"type":"ADVISORY","url":"https://bugzilla.suse.com/show_bug.cgi?id=1237041"},{"type":"REPORT","url":"https://bugzilla.redhat.com/show_bug.cgi?id=2345043"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/openssh/openssh-portable","events":[{"introduced":"0"},{"last_affected":"80a2f64b8c1d27383cc83d182b73920d1e6a91f1"},{"introduced":"0"},{"last_affected":"8241b9c0529228b4b86d88b1a6076fb9f97e4a99"},{"introduced":"0"},{"last_affected":"8241b9c0529228b4b86d88b1a6076fb9f97e4a99"},{"introduced":"0"},{"last_affected":"86bdd3853f4d32c85e295e6216a2fe0953ad93f0"},{"introduced":"0"},{"last_affected":"86bdd3853f4d32c85e295e6216a2fe0953ad93f0"},{"introduced":"0"},{"last_affected":"6849957945754e6551e515f41e8cf3937cda222d"},{"introduced":"0"},{"last_affected":"6849957945754e6551e515f41e8cf3937cda222d"},{"introduced":"0"},{"last_affected":"53a80baaebda180f46e6e8571f3ff800e1f5c496"}],"database_specific":{"versions":[{"introduced":"0"},{"last_affected":"9.5-p1"},{"introduced":"0"},{"last_affected":"9.6-NA"},{"introduced":"0"},{"last_affected":"9.6-p1"},{"introduced":"0"},{"last_affected":"9.7-NA"},{"introduced":"0"},{"last_affected":"9.7-p1"},{"introduced":"0"},{"last_affected":"9.8-NA"},{"introduced":"0"},{"last_affected":"9.8-p1"},{"introduced":"0"},{"last_affected":"9.9-p1"}]}}],"versions":["ABOUT_TO_ADD_INET_ATON","AFTER_FREEBSD_PAM_MERGE","AFTER_KRB5_GSSAPI_MERGE","BEFORE_FREEBSD_PAM_MERGE","BEFORE_KRB5_GSSAPI_MERGE","POST_KRB4_REMOVAL","PRE-REORDER","PRE_CYGWIN_MERGE","PRE_DAN_PATCH_MERGE","PRE_FIXPATHS_INTEGRATION","PRE_HPUX_INTEGRATION","PRE_IPV6","PRE_KRB4_REMOVAL","PRE_NEW_LOGIN_CODE","PRE_SW_KRBV","V_1_2PRE17","V_1_2_1_PRE18","V_1_2_1_PRE19","V_1_2_1_PRE20","V_1_2_1_PRE21","V_1_2_1_PRE22","V_1_2_1_PRE23","V_1_2_1_PRE24","V_1_2_1_PRE25","V_1_2_1_PRE26","V_1_2_1_PRE27","V_1_2_2","V_1_2_2_P1","V_1_2_2_PRE28","V_1_2_2_PRE29","V_1_2_3","V_1_2_3_PRE1","V_1_2_3_PRE2","V_1_2_3_PRE3","V_1_2_3_PRE4","V_1_2_3_PRE5","V_1_2_3_TEST1","V_1_2_3_TEST2","V_1_2_3_TEST3","V_1_2_PRE10","V_1_2_PRE11","V_1_2_PRE12","V_1_2_PRE13","V_1_2_PRE14","V_1_2_PRE15","V_1_2_PRE16","V_1_2_PRE4","V_1_2_PRE5","V_1_2_PRE6","V_1_2_PRE7","V_1_2_PRE8","V_1_2_PRE9","V_2_0_0_BETA1","V_2_0_0_BETA2","V_2_0_0_TEST1","V_2_1_0","V_2_1_0_P1","V_2_1_0_P2","V_2_1_0_P3","V_2_1_1_P1","V_2_1_1_P2","V_2_1_1_P3","V_2_1_1_P4","V_2_2_0_P1","V_2_3_0_P1","V_2_5_0_P1","V_2_5_1_P1","V_2_5_1_P2","V_2_5_2_P1","V_3_0_1_P1","V_3_0_P1","V_3_1_P1","V_3_2_2_P1","V_3_4_P1","V_3_6_1_P1","V_3_8_P1","V_3_9_P1","V_4_2_P1","V_5_0_P1","V_5_1_P1","V_5_2_P1","V_5_5_P1","V_5_7_P1","V_6_0_P1","V_6_1_P1","V_6_2_P1","V_6_5_P1","V_6_6_P1","V_6_8_P1","V_6_9_P1","V_7_0_P1","V_7_1_P1","V_7_2_P1","V_7_3_P1","V_7_4_P1","V_7_5_P1","V_7_6_P1","V_7_7_P1","V_7_8_P1","V_7_9_P1","V_8_0_P1","V_8_1_P1","V_8_2_P1","V_8_4_P1","V_8_5_P1","V_8_6_P1","V_8_7_P1","V_8_8_P1","V_8_9_P1","V_9_0_P1","V_9_1_P1","V_9_2_P1","V_9_3_P1","V_9_5_P1","V_9_6_P1","V_9_7_P1","V_9_8_P1","V_9_9_P1"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-26466.json","unresolved_ranges":[{"events":[{"introduced":"0"},{"last_affected":"9.9-NA"}]},{"events":[{"introduced":"0"},{"last_affected":"24.04"}]},{"events":[{"introduced":"0"},{"last_affected":"24.10"}]},{"events":[{"introduced":"0"},{"last_affected":"11.0"}]},{"events":[{"introduced":"0"},{"last_affected":"12.0"}]},{"events":[{"introduced":"0"},{"last_affected":"13.0"}]}]}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}