{"id":"CVE-2026-9547","summary":"SSH improper host validation","details":"When a libcurl-based application performs transfers via `SCP://` or `SFTP://`\nand utilizes the `CURLOPT_SSH_KEYFUNCTION` callback, it may silently accept an\nuntrusted server. This vulnerability occurs when a server presents a host key\ntype that does not match the specific key type already recorded for that host\nin the `known_hosts` file. Instead of rejecting the mismatch, the callback\nmechanism fails to properly enforce the restriction, allowing the connection\nto succeed without warning and risking a potential man-in-the-middle attack.","aliases":["CURL-CVE-2026-9547"],"modified":"2026-10-24T14:20:56.025498276Z","published":"2026-07-03T06:18:44.499Z","related":["ALSA-2026:55439","SUSE-SU-2026:22553-1","SUSE-SU-2026:22582-1","SUSE-SU-2026:22709-1","SUSE-SU-2026:22889-1","SUSE-SU-2026:2925-1","SUSE-SU-2026:2926-1","SUSE-SU-2026:3043-1","SUSE-SU-2026:3814-1","openSUSE-SU-2026:11230-1","openSUSE-SU-2026:21272-1"],"database_specific":{"cwe_ids":["CWE-297"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/9xxx/CVE-2026-9547.json","cna_assigner":"curl"},"references":[{"type":"WEB","url":"https://curl.se/docs/CVE-2026-9547.html"},{"type":"WEB","url":"https://curl.se/docs/CVE-2026-9547.json"},{"type":"WEB","url":"https://hackerone.com/reports/3751712"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/9xxx/CVE-2026-9547.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-9547"},{"type":"PACKAGE","url":"https://github.com/curl/curl.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/curl/curl","events":[{"introduced":"b8d1366852fd0034374c5de1e4968c7a224f77cc"},{"fixed":"68720b4837284335b2d63cb358f8f6ce65f5bc55"}],"database_specific":{"extracted_events":[{"range":[{"introduced":"7.69.0"},{"fixed":"8.21.0"}],"source":"CPE_RANGE","cpe":"cpe:2.3:a:haxx:curl:*:*:*:*:*:*:*:*"}]}},{"type":"GIT","repo":"https://github.com/curl/curl.git","events":[{"introduced":"507cf6a13db0375eadd4655b4c64710db29e9cf2"},{"fixed":"0b8dbbc63c98777e4584cb9fbd71df3464008ad1"}],"database_specific":{"extracted_events":[{"range":[{"introduced":"507cf6a13db0375eadd4655b4c64710db29e9cf2"},{"fixed":"0b8dbbc63c98777e4584cb9fbd71df3464008ad1"}],"source":"AFFECTED_FIELD","strategy":"StandardRange"}]}}],"versions":["7.69.0","7.69.1","7.70.0","7.71.0","7.71.1","7.72.0","7.73.0","7.74.0","7.75.0","7.76.0","7.76.1","7.77.0","7.78.0","7.79.0","7.79.1","7.80.0","7.81.0","7.82.0","7.83.0","7.83.1","7.84.0","7.85.0","7.86.0","7.87.0","7.88.0","7.88.1","8.0.0","8.0.1","8.1.0","8.1.1","8.1.2","8.10.0","8.10.1","8.11.0","8.11.1","8.12.0","8.12.1","8.13.0","8.14.0","8.14.1","8.15.0","8.16.0","8.17.0","8.18.0","8.19.0","8.2.0","8.2.1","8.20.0","8.3.0","8.4.0","8.5.0","8.6.0","8.7.0","8.7.1","8.8.0","8.9.0","8.9.1","rc-8_21_0-3","rc-8_21_0-2","rc-8_21_0-1","curl-8_20_0","rc-8_20_0-3","rc-8_20_0-2","rc-8_20_0-1","curl-8_19_0","curl-8_18_0","curl-8_17_0","curl-8_16_0","curl-8_15_0","curl-8_14_1","curl-8_14_0","curl-8_13_0","curl-8_12_1","curl-8_12_0","curl-8_11_1","curl-8_11_0","curl-8_10_1","curl-8_10_0","curl-8_9_1","curl-8_9_0","curl-8_8_0","curl-8_7_1","curl-8_7_0","curl-8_6_0","curl-8_5_0","curl-8_4_0","curl-8_3_0","curl-8_2_1","curl-8_2_0","curl-8_1_2","curl-8_1_1","curl-8_1_0","curl-8_0_1","curl-8_0_0","curl-7_88_1","curl-7_88_0","curl-7_87_0","curl-7_86_0","curl-7_85_0","curl-7_84_0","curl-7_83_1","curl-7_83_0","curl-7_82_0","curl-7_81_0","curl-7_80_0","curl-7_79_1","curl-7_79_0","curl-7_78_0","curl-7_77_0","curl-7_76_1","curl-7_76_0","curl-7_75_0","curl-7_74_0","curl-7_73_0","curl-7_72_0","curl-7_71_1","curl-7_71_0","curl-7_70_0","curl-7_69_1","curl-7_69_0","rc-8_19_0-3","rc-8_19_0-2","rc-8_19_0-1","rc-8_18_0-3","rc-8_18_0-2","rc-8_18_0-1"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-9547.json","vanir_signatures":[{"digest":{"length":4615,"function_hash":"171591672620915120098914005398439744356"},"id":"CVE-2026-9547-e5ddacc0","signature_type":"Function","signature_version":"v1","source":"https://github.com/curl/curl.git/commit/0b8dbbc63c98777e4584cb9fbd71df3464008ad1","target":{"file":"lib/vssh/libssh.c","function":"myssh_is_known"},"deprecated":false},{"id":"CVE-2026-9547-ffd5c5b3","signature_type":"Line","signature_version":"v1","source":"https://github.com/curl/curl.git/commit/0b8dbbc63c98777e4584cb9fbd71df3464008ad1","target":{"file":"lib/vssh/libssh.c"},"deprecated":false,"digest":{"line_hashes":["19522727956082994505377891717732253881","17505745399782688697084999810884215111","65466782891270922555303879365870593631","39998244195617753293703183793609467932"],"threshold":0.9}}],"vanir_signatures_modified":"2026-10-24T14:20:56Z"}}],"schema_version":"1.9.2","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N"}]}