{"id":"CVE-2025-27498","aliases":["EUVD-2025-5557","GHSA-r38m-44fw-h886","UBUNTU-CVE-2025-27498"],"status":"published","title":"AEADs/ascon-aead: Plaintext exposed in decrypt_in_place_detached even on tag verification failure","description":"aes-gcm is a pure Rust implementation of the AES-GCM. In decrypt_in_place_detached, the decrypted ciphertext (which is the correct ciphertext) is exposed even if the tag is incorrect. This is because in decrypt_inplace in asconcore.rs, tag verification causes an error to be returned with the plaintext contents still in buffer. The vulnerability is fixed in 0.4.3.","severity":{"version":"4.0","score":5.6,"vector":"CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:A/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00125,"percentile":0.0227,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-347"],"published":"2025-03-03T16:52:02Z","modified":"2026-10-28T02:30:27Z","fixes":[{"ecosystem":"crates.io","package":"ascon_aead","fixed_in":["0.4.3"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"crates.io","package":"ascon_aead","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"0.4.2"},{"fixed":"0.4.3"}]}]},{"source":"osv","ecosystem":"crates.io","package":"ascon_aead","ranges":[{"type":"SEMVER","events":[{"introduced":"0"},{"fixed":"0.4.3"}]}]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"rust-aes-gcm","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.10.3-1","0.10.3-2"]},{"source":"osv","ecosystem":"Ubuntu:25.10","package":"rust-aes-gcm","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.10.3-2"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"rust-aes-gcm","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.10.3-2","0.11.0-1"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"rust-aes-gcm","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["0.10.3-2"]}],"products":[{"vendor":"rustcrypto","product":"aeads"}],"references":[{"url":"https://github.com/RustCrypto/AEADs/security/advisories/GHSA-r38m-44fw-h886","tags":["x_refsource_CONFIRM","advisory","web","report"]},{"url":"https://github.com/RustCrypto/AEADs/commit/d1d749ba57e38e65b0e037cd744d0b17f7254037","tags":["x_refsource_MISC","fix","web","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-27498","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-r38m-44fw-h886"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/27xxx/CVE-2025-27498.json","tags":["advisory"]},{"url":"https://github.com/RustCrypto/AEADs","tags":["package"]},{"url":"https://ubuntu.com/security/CVE-2025-27498","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2025-27498","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2025-27498","title":"AEADs/ascon-aead: Plaintext exposed in decrypt_in_place_detached even on tag verification failure","description":"aes-gcm is a pure Rust implementation of the AES-GCM. In decrypt_in_place_detached, the decrypted ciphertext (which is the correct ciphertext) is exposed even if the tag is incorrect. This is because in decrypt_inplace in asconcore.rs, tag verification causes an error to be returned with the plaintext contents still in buffer. The vulnerability is fixed in 0.4.3.","status":"published","published":"2025-03-03T16:52:02.75Z","modified":"2025-03-03T17:32:24.64Z","cvss":[{"version":"4.0","score":5.6,"vector":"CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:A/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N","level":"medium","assessor":"cna"}],"cwes":["CWE-347"],"updated_at":"2026-11-02T14:32:42.751171Z"}],"euvd":[{"id":"EUVD-2025-5557","description":"aes-gcm is a pure Rust implementation of the AES-GCM. In decrypt_in_place_detached, the decrypted ciphertext (which is the correct ciphertext) is exposed even if the tag is incorrect. This is because in decrypt_inplace in asconcore.rs, tag verification causes an error to be returned with the plaintext contents still in buffer. The vulnerability is fixed in 0.4.3.","status":"published","published":"2025-03-03T16:52:02Z","modified":"2025-03-03T17:32:24Z","cvss":[{"version":"4.0","score":5.6,"vector":"CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:A/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-02T20:53:18.061162Z"}],"ghsa":[{"id":"GHSA-r38m-44fw-h886","title":"AEADs/ascon-aead: Plaintext exposed in decrypt_in_place_detached even on tag verification failure","description":"### Summary\nIn `decrypt_in_place_detached`, the decrypted ciphertext (which is the correct ciphertext) is exposed even if the tag is incorrect.\n\n### Details\nThis is because in [decrypt_inplace](https://github.com/RustCrypto/AEADs/blob/8cda109f1128c4c7953a0bb0f53e1056d537e462/ascon-aead/src/asconcore.rs#L350-L364) in asconcore.rs, tag verification causes an error to be returned with the plaintext contents still in `buffer`. The root cause of this vulnerability is similar to https://github.com/RustCrypto/AEADs/security/advisories/GHSA-423w-p2w9-r7vq\n\n### PoC\n```rust\nuse ascon_aead::Tag;\nuse ascon_aead::{Ascon128, Key, Nonce};\nuse ascon_aead::aead::{AeadInPlace, KeyInit};\n\nfn main() {\n\n    let key = Key::\u003cAscon128\u003e::from_slice(b\"very secret key.\");\n    let cipher = Ascon128::new(key);\n\n    let nonce = Nonce::\u003cAscon128\u003e::from_slice(b\"unique nonce 012\"); // 128-bits; unique per message\n\n    let mut buffer: Vec\u003cu8\u003e = Vec::new(); // Buffer needs 16-bytes overhead for authentication tag\n    buffer.extend_from_slice(b\"plaintext message\");\n\n    // Encrypt `buffer` in-place detached, replacing the plaintext contents with ciphertext\n    cipher.encrypt_in_place_detached(nonce, b\"\", \u0026mut buffer).expect(\"encryption failure!\");\n    \n    // Decrypt `buffer` in-place with the wrong tag, ignoring the decryption error\n    let _ = cipher.decrypt_in_place_detached(nonce, b\"\", \u0026mut buffer, Tag::\u003cAscon128\u003e::from_slice(b\"\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\"));\n\n    assert_eq!(\u0026buffer, b\"plaintext message\");\n}\n```\n### Impact\nIf a program continues to use the result of `decrypt_in_place_detached` after a decryption failure, the result will be unauthenticated. This may permit some forms of chosen ciphertext attacks (CCAs).","status":"published","published":"2025-03-03T20:22:19Z","modified":"2025-03-03T20:22:20Z","cvss":[{"version":"4.0","score":5.7,"vector":"CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:A/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"cwes":["CWE-347"],"updated_at":"2026-11-02T14:38:33.163519Z"}],"nvd":[{"id":"CVE-2025-27498","description":"aes-gcm is a pure Rust implementation of the AES-GCM. In decrypt_in_place_detached, the decrypted ciphertext (which is the correct ciphertext) is exposed even if the tag is incorrect. This is because in decrypt_inplace in asconcore.rs, tag verification causes an error to be returned with the plaintext contents still in buffer. The vulnerability is fixed in 0.4.3.","status":"published","published":"2025-03-03T17:15:16.443Z","modified":"2026-06-17T09:03:42.923Z","cvss":[{"version":"4.0","score":5.7,"vector":"CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:A/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"}],"cwes":["CWE-347"],"updated_at":"2026-11-02T14:10:52.398004Z"}],"osv":[{"id":"CVE-2025-27498","title":"AEADs/ascon-aead: Plaintext exposed in decrypt_in_place_detached even on tag verification failure","description":"aes-gcm is a pure Rust implementation of the AES-GCM. In decrypt_in_place_detached, the decrypted ciphertext (which is the correct ciphertext) is exposed even if the tag is incorrect. This is because in decrypt_inplace in asconcore.rs, tag verification causes an error to be returned with the plaintext contents still in buffer. The vulnerability is fixed in 0.4.3.","status":"published","published":"2025-03-03T16:52:02.75Z","modified":"2026-10-28T02:30:27.847224512Z","cvss":[{"version":"4.0","score":5.6,"vector":"CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:A/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"cwes":["CWE-347"],"updated_at":"2026-11-02T15:44:47.708311Z"},{"id":"GHSA-r38m-44fw-h886","title":"AEADs/ascon-aead: Plaintext exposed in decrypt_in_place_detached even on tag verification failure","description":"### Summary\nIn `decrypt_in_place_detached`, the decrypted ciphertext (which is the correct ciphertext) is exposed even if the tag is incorrect.\n\n### Details\nThis is because in [decrypt_inplace](https://github.com/RustCrypto/AEADs/blob/8cda109f1128c4c7953a0bb0f53e1056d537e462/ascon-aead/src/asconcore.rs#L350-L364) in asconcore.rs, tag verification causes an error to be returned with the plaintext contents still in `buffer`. The root cause of this vulnerability is similar to https://github.com/RustCrypto/AEADs/security/advisories/GHSA-423w-p2w9-r7vq\n\n### PoC\n```rust\nuse ascon_aead::Tag;\nuse ascon_aead::{Ascon128, Key, Nonce};\nuse ascon_aead::aead::{AeadInPlace, KeyInit};\n\nfn main() {\n\n    let key = Key::\u003cAscon128\u003e::from_slice(b\"very secret key.\");\n    let cipher = Ascon128::new(key);\n\n    let nonce = Nonce::\u003cAscon128\u003e::from_slice(b\"unique nonce 012\"); // 128-bits; unique per message\n\n    let mut buffer: Vec\u003cu8\u003e = Vec::new(); // Buffer needs 16-bytes overhead for authentication tag\n    buffer.extend_from_slice(b\"plaintext message\");\n\n    // Encrypt `buffer` in-place detached, replacing the plaintext contents with ciphertext\n    cipher.encrypt_in_place_detached(nonce, b\"\", \u0026mut buffer).expect(\"encryption failure!\");\n    \n    // Decrypt `buffer` in-place with the wrong tag, ignoring the decryption error\n    let _ = cipher.decrypt_in_place_detached(nonce, b\"\", \u0026mut buffer, Tag::\u003cAscon128\u003e::from_slice(b\"\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\\x00\"));\n\n    assert_eq!(\u0026buffer, b\"plaintext message\");\n}\n```\n### Impact\nIf a program continues to use the result of `decrypt_in_place_detached` after a decryption failure, the result will be unauthenticated. This may permit some forms of chosen ciphertext attacks (CCAs).","status":"published","published":"2025-03-03T20:22:19Z","modified":"2025-03-03T20:42:06.139683Z","cvss":[{"version":"4.0","score":5.6,"vector":"CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:A/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"cwes":["CWE-347"],"updated_at":"2026-11-02T15:46:55.122811Z"},{"id":"UBUNTU-CVE-2025-27498","description":"aes-gcm is a pure Rust implementation of the AES-GCM. In decrypt_in_place_detached, the decrypted ciphertext (which is the correct ciphertext) is exposed even if the tag is incorrect. This is because in decrypt_inplace in asconcore.rs, tag verification causes an error to be returned with the plaintext contents still in buffer. The vulnerability is fixed in 0.4.3.","status":"published","published":"2025-03-03T17:15:00Z","modified":"2026-10-17T12:56:48.991299855Z","cvss":[{"version":"4.0","score":5.6,"vector":"CVSS:4.0/AV:L/AC:H/AT:N/PR:N/UI:A/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-02T16:55:26.330196Z"}]}}