{"id":"CVE-2025-66442","aliases":["DEBIAN-CVE-2025-66442","EUVD-2025-209171","GHSA-56v8-wv3m-qgg6","JLSEC-2026-463","UBUNTU-CVE-2025-66442"],"status":"published","title":"In Mbed TLS through 4.0.0, there is a compiler-induced timing side channel (in RSA and CBC/ECB...","description":"In Mbed TLS through 4.0.0, there is a compiler-induced timing side channel (in RSA and CBC/ECB decryption) that only occurs with LLVM's select-optimize feature. TF-PSA-Crypto through 1.0.0 is also affected.","severity":{"version":"3.1","score":5.1,"vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium","assessor":"adp","from":"cve"},"epss":{"day":"2026-11-12","score":0.0028,"percentile":0.20772,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-385"],"published":"2026-04-01T00:00:00Z","modified":"2026-11-05T10:01:10Z","affected":[{"source":"osv","ecosystem":"Debian:12","package":"mbedtls","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.28.3-1","2.28.4-1","2.28.5-1","2.28.6-1","2.28.7-1","2.28.7-1.1","2.28.7-1.1~exp1","2.28.8-1","3.6.0-1","3.6.0-2","3.6.0-3","3.6.2-1","3.6.2-2","3.6.2-3","3.6.3-1","3.6.4-1","3.6.4-2","3.6.5-0.1","3.6.5-0.1~deb13u1","3.6.6-0.1","3.6.6-0.1~deb13u1","3.6.7-2","3.6.7-3"]},{"source":"osv","ecosystem":"Debian:13","package":"mbedtls","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.6.4-2","3.6.5-0.1","3.6.5-0.1~deb13u1","3.6.6-0.1","3.6.6-0.1~deb13u1","3.6.7-2","3.6.7-3"]},{"source":"osv","ecosystem":"Debian:14","package":"mbedtls","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.6.4-2","3.6.5-0.1","3.6.5-0.1~deb13u1","3.6.6-0.1","3.6.6-0.1~deb13u1","3.6.7-2","3.6.7-3"]},{"source":"osv","ecosystem":"Julia","package":"MbedTLS_jll","ranges":[{"type":"SEMVER","events":[{"introduced":"0"}]}]},{"source":"osv","ecosystem":"Ubuntu:16.04:LTS","package":"mbedtls","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.1.2-1","2.2.0-1","2.2.1-1","2.2.1-2","2.2.1-2ubuntu0.1","2.2.1-2ubuntu0.2","2.2.1-2ubuntu0.3"]},{"source":"osv","ecosystem":"Ubuntu:Pro:18.04:LTS","package":"mbedtls","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.5.1-1ubuntu1","2.6.0-1","2.7.0-2","2.8.0-1","2.8.0-1ubuntu0.1~esm1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:20.04:LTS","package":"mbedtls","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.16.2-1","2.16.3-1","2.16.4-1ubuntu2","2.16.4-1ubuntu2+esm1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:22.04:LTS","package":"mbedtls","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.16.9-0.1ubuntu1","2.16.11-0.1ubuntu1","2.16.11-0.3","2.28.0-1","2.28.0-1build1","2.28.0-1ubuntu0.1~esm1"]},{"source":"osv","ecosystem":"Ubuntu:Pro:24.04:LTS","package":"mbedtls","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.28.3-1","2.28.6-1ubuntu1","2.28.7-1ubuntu1","2.28.7-1.1ubuntu1","2.28.8-1","2.28.8-1ubuntu0.1~esm1"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"mbedtls","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.6.2-3ubuntu1"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"mbedtls","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.6.5-0.1ubuntu2","3.6.6-0.1ubuntu1","3.6.7-3ubuntu1"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"mbedtls","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["3.6.2-3ubuntu1","3.6.5-0.1ubuntu1","3.6.5-0.1ubuntu2"]}],"products":[{"vendor":"arm","product":"mbed_tls"},{"vendor":"arm","product":"tf-psa-crypto"}],"references":[{"url":"https://github.com/Mbed-TLS/mbedtls/releases","tags":["Release Notes","package","web","report"]},{"url":"https://mbed-tls.readthedocs.io/en/latest/security-advisories/","tags":["Vendor Advisory","advisory","web","report"]},{"url":"https://github.com/Mbed-TLS/TF-PSA-Crypto/releases","tags":["Release Notes","package","web","report"]},{"url":"https://mbed-tls.readthedocs.io/en/latest/security-advisories/mbedtls-security-advisory-2026-03-compiler-induced-constant-time-violations/","tags":["Vendor Advisory","advisory","web","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-66442","tags":["advisory"]},{"url":"https://mbed-tls.readthedocs.io/en/latest/security-advisories"},{"url":"https://mbed-tls.readthedocs.io/en/latest/security-advisories/mbedtls-security-advisory-2026-03-compiler-induced-constant-time-violations"},{"url":"https://github.com/advisories/GHSA-56v8-wv3m-qgg6"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/66xxx/CVE-2025-66442.json","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2025-66442","tags":["advisory"]},{"url":"https://ubuntu.com/security/CVE-2025-66442","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2025-66442","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2025-66442","description":"In Mbed TLS through 4.0.0, there is a compiler-induced timing side channel (in RSA and CBC/ECB decryption) that only occurs with LLVM's select-optimize feature. TF-PSA-Crypto through 1.0.0 is also affected.","status":"published","published":"2026-04-01T00:00:00Z","modified":"2026-04-01T20:00:06.815Z","cvss":[{"version":"3.1","score":5.1,"vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium","assessor":"adp"}],"cwes":["CWE-385"],"updated_at":"2026-11-02T14:32:53.157279Z"}],"euvd":[{"id":"EUVD-2025-209171","description":"In Mbed TLS through 4.0.0, there is a compiler-induced timing side channel (in RSA and CBC/ECB decryption) that only occurs with LLVM's select-optimize feature. TF-PSA-Crypto through 1.0.0 is also affected.","status":"published","published":"2026-04-01T00:00:00Z","modified":"2026-04-01T20:00:06Z","cvss":[{"version":"3.1","score":5.1,"vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T19:25:23.620594Z"}],"ghsa":[{"id":"GHSA-56v8-wv3m-qgg6","title":"In Mbed TLS through 4.0.0, there is a compiler-induced timing side channel (in RSA and CBC/ECB...","description":"In Mbed TLS through 4.0.0, there is a compiler-induced timing side channel (in RSA and CBC/ECB decryption) that only occurs with LLVM's select-optimize feature. TF-PSA-Crypto through 1.0.0 is also affected.","status":"published","published":"2026-04-01T21:30:30Z","modified":"2026-04-01T21:30:38Z","cvss":[{"version":"3.1","score":5.1,"vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"cwes":["CWE-385"],"updated_at":"2026-11-02T15:07:04.885246Z"}],"nvd":[{"id":"CVE-2025-66442","description":"In Mbed TLS through 4.0.0, there is a compiler-induced timing side channel (in RSA and CBC/ECB decryption) that only occurs with LLVM's select-optimize feature. TF-PSA-Crypto through 1.0.0 is also affected.","status":"published","published":"2026-04-01T20:16:22.107Z","modified":"2026-11-04T22:10:00.21Z","cvss":[{"version":"3.1","score":5.1,"vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-385"],"updated_at":"2026-11-04T23:43:38.567042Z"}],"osv":[{"id":"CVE-2025-66442","description":"In Mbed TLS through 4.0.0, there is a compiler-induced timing side channel (in RSA and CBC/ECB decryption) that only occurs with LLVM's select-optimize feature. TF-PSA-Crypto through 1.0.0 is also affected.","status":"published","published":"2026-04-01T00:00:00Z","modified":"2026-11-12T02:45:56.976451986Z","cvss":[{"version":"3.1","score":5.1,"vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"updated_at":"2026-11-07T11:15:38.581573Z"},{"id":"DEBIAN-CVE-2025-66442","description":"In Mbed TLS through 4.0.0, there is a compiler-induced timing side channel (in RSA and CBC/ECB decryption) that only occurs with LLVM's select-optimize feature. TF-PSA-Crypto through 1.0.0 is also affected.","status":"published","published":"2026-04-01T20:16:22.107Z","modified":"2026-11-05T10:01:10.267715642Z","cvss":[{"version":"3.1","score":5.1,"vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"updated_at":"2026-11-05T13:31:24.64316Z"},{"id":"JLSEC-2026-463","title":"Mbed TLS timing side channel in RSA and CBC/ECB decryption","description":"In Mbed TLS through 4.0.0, there is a compiler-induced timing side channel (in RSA and CBC/ECB decryption) that only occurs with LLVM's select-optimize feature. TF-PSA-Crypto through 1.0.0 is also affected.","status":"published","published":"2026-05-07T16:17:33.752Z","modified":"2026-07-18T00:02:03.411261137Z","cvss":[{"version":"3.1","score":5.1,"vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T15:47:18.573531Z"},{"id":"UBUNTU-CVE-2025-66442","description":"In Mbed TLS through 4.0.0, there is a compiler-induced timing side channel (in RSA and CBC/ECB decryption) that only occurs with LLVM's select-optimize feature. TF-PSA-Crypto through 1.0.0 is also affected.","status":"published","published":"2026-04-01T20:16:00Z","modified":"2026-10-17T12:57:29.342270476Z","cvss":[{"version":"3.1","score":5.1,"vector":"CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N","level":"medium"}],"updated_at":"2026-11-02T16:55:52.345622Z"}]}}