{"id":"CVE-2026-69184","summary":"c-ares: CPU-exhaustion denial of service via unbounded DNS name compression pointer chains","details":"c-ares is an asynchronous resolver library. Prior to 1.34.7, ares_dns_name_parse() enforces backward DNS compression pointers but does not bound the total pointer hops or assembled name length. A malicious DNS server can send a response containing a long descending pointer chain and many resource records whose NAME or RDATA fields refer to the chain, causing repeated decompression work that grows quadratically with message size. A single crafted response can stall the single-threaded c-ares event loop and deny DNS resolution, without causing memory corruption or information disclosure. This issue is fixed in version 1.34.7.","aliases":["GHSA-pjmc-gx33-gc76"],"modified":"2026-09-20T08:19:49.354326Z","published":"2026-09-18T17:26:52.210Z","related":["SUSE-SU-2026:23364-1","SUSE-SU-2026:23414-1","SUSE-SU-2026:3872-1","SUSE-SU-2026:4021-1","openSUSE-SU-2026:11593-1","openSUSE-SU-2026:21721-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/69xxx/CVE-2026-69184.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-407"]},"references":[{"type":"WEB","url":"https://github.com/c-ares/c-ares/releases/tag/v1.34.7"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/69xxx/CVE-2026-69184.json"},{"type":"ADVISORY","url":"https://github.com/c-ares/c-ares/security/advisories/GHSA-pjmc-gx33-gc76"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-69184"},{"type":"FIX","url":"https://github.com/c-ares/c-ares/commit/5c8341ba6ff3a8e4e4dfd616f8ed0418838b8b7b"},{"type":"FIX","url":"https://github.com/c-ares/c-ares/commit/f1288bbc70e9a1e0a77134c2382157e52d326aea"},{"type":"FIX","url":"https://github.com/c-ares/c-ares/pull/1164"},{"type":"FIX","url":"https://github.com/c-ares/c-ares/pull/1210"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/c-ares/c-ares","events":[{"introduced":"0"},{"fixed":"5c8341ba6ff3a8e4e4dfd616f8ed0418838b8b7b"},{"fixed":"f1288bbc70e9a1e0a77134c2382157e52d326aea"},{"fixed":"d63b7de3a3568d14ab1351374b205365aed51cca"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"1.34.7"}],"source":["AFFECTED_FIELD","REFERENCES"]}}],"versions":["v1.34.6","v1.34.5","v1.34.4","v1.34.3","v1.34.2","v1.34.1","v1.34.0","v1.31.0","cares-1_29_0","cares-1_28_1","cares-1_28_0","cares-1_27_0","cares-1_26_0","cares-1_25_0","cares-1_24_0","cares-1_23_0","cares-1_22_1","cares-1_22_0","cares-1_21_0","cares-1_20_1","cares-1_20_0","cares-1_19_1","cares-1_19_0","cares-1_18_1","cares-1_18_0","cares-1_17_2","cares-1_17_1","c-ares-1_17_0","cares-1_16_1","cares-1_16_0","cares-1_15_0","cares-1_14_0","cares-1_13_0","cares-1_12_0","cares-1_11_0","cares-1_11_0-rc1","cares-1_10_0","cares-1_9_1","cares-1_9_0","cares-1_8_0","cares-1_7_5","cares-1_7_4","cares-1_7_3","cares-1_7_2","cares-1_7_1","curl-7_20_0","cares-1_7_0","curl-7_19_7","curl-7_19_6","curl-7_19_5","curl-7_19_4","curl-7_19_3","cares-1_6_0","curl-7_19_2","curl-7_19_0","cares-1_5_3","curl-7_18_2","cares-1_5_2","curl-7_18_1","curl-7_18_0","cares-1_5_1","cares-1_5_0","curl-7_17_1","curl-7_17_0","curl-7_16_4","curl-7_16_3","cares-1_4_0","curl-7_16_2","curl-7_16_1","cares-1_3_2","curl-7_16_0","curl-7_15_6-prepipeline","curl-7_15_5","cares-1_3_1","curl-7_15_4","curl-7_15_3","curl-7_15_1","curl-7_15_0","curl-7_14_1","curl-7_14_0","curl-7_13_2","curl-7_13_1","curl-7_13_0","cares-1_2_1","curl-7_12_2","curl-7_12_1","curl-7_12_0","c-ares-1_2_0","curl-7_11_1","cares-1_1_0","curl-7_11_0","curl-7_10_8"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-69184.json","vanir_signatures_modified":"2026-09-20T08:19:49Z","vanir_signatures":[{"source":"https://github.com/c-ares/c-ares/commit/5c8341ba6ff3a8e4e4dfd616f8ed0418838b8b7b","target":{"file":"src/lib/record/ares_dns_name.c","function":"ares_nameoffset_create"},"deprecated":false,"digest":{"function_hash":"215120991549543867585004465135371789693","length":744},"id":"CVE-2026-69184-2889431b","signature_type":"Function","signature_version":"v1"},{"id":"CVE-2026-69184-4d04b6bb","signature_type":"Function","signature_version":"v1","source":"https://github.com/c-ares/c-ares/commit/f1288bbc70e9a1e0a77134c2382157e52d326aea","target":{"file":"src/lib/record/ares_dns_name.c","function":"ares_split_dns_name"},"deprecated":false,"digest":{"function_hash":"63769790708184396424190549000564986090","length":1533}},{"target":{"file":"src/lib/record/ares_dns_name.c"},"deprecated":false,"digest":{"line_hashes":["331059929832393892051021650276169864340","313307373139565117197713984883681038497","21510539917802293962719951365905549209","259935751308194948445369237931411112494","74076514307914947545122739126975926579","7151332547064102914099214739226155832","103244722270367619701122181715443323039","135244659067020709404793626897388314248","90855899157933052063971711592145095201","22526826157164293655680641129629101447","251273078756938416859181967133295633185","277907088208683694084886859820662666993","48905434183268375001597202232202922831","28893845586004648671976909245382097888","243752068252325868323499696657518052185","245898895283352357465325419255396950155","99660406194303193866841561934420775326","333678538892689436203979424784471818519","130002018225106014266392409173048146789"],"threshold":0.9},"id":"CVE-2026-69184-51191c96","signature_type":"Line","signature_version":"v1","source":"https://github.com/c-ares/c-ares/commit/f1288bbc70e9a1e0a77134c2382157e52d326aea"},{"id":"CVE-2026-69184-55c8e212","signature_type":"Line","signature_version":"v1","source":"https://github.com/c-a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