{"id":"CVE-2026-12816","summary":"IESEngine stream-mode MAC forgery via length-dependent KDF split","details":"In Bouncy Castle for Java before 1.85, IESEngine stream-mode MAC forgery via length-dependent KDF split. This issue also affects Bouncy Castle for Java LTS before 2.73.12.","modified":"2026-08-14T18:56:20.700198807Z","published":"2026-08-03T02:53:32.240Z","related":["SUSE-SU-2026:23127-1","SUSE-SU-2026:23150-1","SUSE-SU-2026:3559-1","openSUSE-SU-2026:11445-1","openSUSE-SU-2026:21538-1"],"database_specific":{"cna_assigner":"bcorg","cwe_ids":["CWE-354"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/12xxx/CVE-2026-12816.json"},"references":[{"type":"WEB","url":"https://www.bouncycastle.org/download/bouncy-castle-java-lts/"},{"type":"WEB","url":"https://www.bouncycastle.org/download/bouncy-castle-java/"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/12xxx/CVE-2026-12816.json"},{"type":"ADVISORY","url":"https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%9012816"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-12816"},{"type":"FIX","url":"https://github.com/bcgit/bc-java/commit/6d9e4bbaee9409713ada167e5f901554cbb084ac"},{"type":"PACKAGE","url":"https://github.com/bcgit/bc-java"},{"type":"PACKAGE","url":"https://github.com/bcgit/bc-lts-java"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/bcgit/bc-java","events":[{"introduced":"0"},{"fixed":"57fbd3c501f7a369f64eda311d6a709fc0bcae84"},{"fixed":"6d9e4bbaee9409713ada167e5f901554cbb084ac"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"1.85"}],"source":["DESCRIPTION","REFERENCES"]}},{"type":"GIT","repo":"https://github.com/bcgit/bc-lts-java","events":[{"introduced":"468b5082f3f0971e80bf9edb7029c17b39b9ba0c"},{"fixed":"f101b232c5d3e07ecdd504210a57e43831d6cd65"}],"database_specific":{"extracted_events":[{"introduced":"2.73.0"},{"fixed":"2.73.12"}],"source":"AFFECTED_FIELD"}}],"versions":["r1rv84","r1rv81","r1rv83","r1rv82","r1rv80","r1rv78","r1rv77","r1rv76","r1rv75","r1rv74","r1rv73","r2rv73dot11","r2rv73dot10","r2rv73dot9","r2rv73dot8","r2rv73dot6","r2rv73dot4","r2rv73dot3","r2rv73dot1","r2rv73dot0"],"database_specific":{"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-12816.json","vanir_signatures_modified":"2026-08-12T15:33:29Z","vanir_signatures":[{"deprecated":false,"digest":{"line_hashes":["12286259687050575229296683165244447642","333777176401813269484024012765568856142","169527211862627727946266417483850304161","273074089352199553117741146448631648083","301734875555428388806683935126952525546","109391545642665904104121926837062339161","329942142184009405323326196099659975311","82672375765569238414935117013073813271","316667336811007258297602574029218181368","176536389688541304813118096142318710078"],"threshold":0.9},"id":"CVE-2026-12816-228f0e71","signature_type":"Line","signature_version":"v1","source":"https://github.com/bcgit/bc-java/commit/6d9e4bbaee9409713ada167e5f901554cbb084ac","target":{"file":"core/src/test/java/org/bouncycastle/crypto/test/ECIESTest.java"}},{"source":"https://github.com/bcgit/bc-java/commit/6d9e4bbaee9409713ada167e5f901554cbb084ac","target":{"file":"core/src/main/java/org/bouncycastle/crypto/engines/IESEngine.java"},"deprecated":false,"digest":{"line_hashes":["293969212190527329221926637732999916368","41499694834007515671395711484743739887","64827145259641411542131372628914071863","180367721764810433593426828327176598326","168436458250902241175230047162984817923","132132251421550024796370799550294755915","58603157903586708812716014904207906604","1513752492766316727298870644893712412","261739843364149528787291411753744630007","269753771756450133595081107522174968254","233653678296904439779522386053376593136","244637652468920807298634032480762129996","38064928630513668236892097846663250388","274091415540700430860534070677973595895","175586789904551005474581485595897139352","158087558957549840588140505560366903300","180367721764810433593426828327176598326","168436458250902241175230047162984817923","132132251421550024796370799550294755915","58603157903586708812716014904207906604","1513752492766316727298870644893712412","261739843364149528787291411753744630007","269753771756450133595081107522174968254","233653678296904439779522386053376593136","58776290462259345479804900066229945703","105988070880264724867591314110613282614","48197964834373264991007164130497019958","250237296400504758329293754435434615416","323887388262990516327055875232228152350"],"threshold":0.9},"id":"CVE-2026-12816-4f7e35fb","signature_type":"Line","signature_version":"v1"},{"signature_version":"v1","source":"https://github.com/bcgit/bc-java/commit/6d9e4bbaee9409713ada167e5f901554cbb084ac","target":{"function":"encryptBlock","file":"core/src/main/java/org/bouncycastle/crypto/engines/IESEngine.java"},"deprecated":false,"digest":{"function_hash":"292371127808127455713179976016968776936","length":2105},"id":"CVE-2026-12816-51dbd394","signature_type":"Function"},{"digest":{"function_hash":"320278328325647757176244077734801042929","length":2365},"id":"CVE-2026-12816-932fa2a2","signature_type":"Function","signature_version":"v1","source":"https://git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