CVE-2026-63567
- Source
- https://cve.org/CVERecord?id=CVE-2026-63567
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63567.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2026-63567
- Published
- 2026-10-02T06:58:32Z
- Modified
- 2026-10-29T02:48:32Z
- Severity
-
- 8.2 (High) CVSS_V4 - CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N CVSS Calculator
- Summary
- IesEngine block-cipher mode checks padding before MAC (CBC padding oracle)
- Details
-
Observable discrepancy in IesEngine.DecryptBlock in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote attacker who has captured an IES or ECIES ciphertext, and who can submit modified ciphertexts for decryption under the same key pair, to recover its plaintext via a CBC padding-oracle attack, because in block-cipher mode the engine decrypts the ciphertext and removes its padding before verifying the MAC. A padding failure is therefore reported with a different error message, and without the MAC computation, compared with a MAC failure. Only applications that construct IesEngine directly with a padded block cipher, such as AES in CBC mode with PKCS#7 padding, are affected; stream-mode IES is not.
- Database specific
{ "cna_assigner": "bcorg", "cwe_ids": [ "CWE-203" ], "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63567.json" }- References
-
- https://www.nuget.org/packages/BouncyCastle.Cryptography
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63567.json
- https://github.com/bcgit/bc-csharp/wiki/CVE-2026-63567
- https://nvd.nist.gov/vuln/detail/CVE-2026-63567
- https://github.com/bcgit/bc-csharp/commit/eaa42e1e8125b3e2e25e365c4194c7cd5932360b
- https://github.com/bcgit/bc-csharp/commit/f881400b761134160ec2a05fd27c3e569453788d
- https://github.com/bcgit/bc-csharp
Affected packages
Git / github.com/bcgit/bc-csharp
Affected ranges
- Type
- GIT
- Repo
- https://github.com/bcgit/bc-csharp
- Events
-
Introduced0 Unknown introduced commit / All previous commits are affectedFixedFixedFixed
- Database specific
-
Show details
{ "extracted_events": [ { "cpe": "cpe:2.3:a:bouncycastle:bc-csharp:*:*:*:*:*:*:*:*", "range": [ { "introduced": "0" }, { "fixed": "2.7.0" } ], "source": "CPE_RANGE" }, { "range": [ { "fixed": "eaa42e1e8125b3e2e25e365c4194c7cd5932360b" } ], "source": "REFERENCES_COMMIT" }, { "range": [ { "fixed": "f881400b761134160ec2a05fd27c3e569453788d" } ], "source": "REFERENCES_COMMIT" } ] }
Affected versions
release-1.*
release-1.8.0
release-1.8.0-RC.1
release-1.8.0-RC.2
release-1.8.0-RC.3
release-1.8.0-beta.1
release-1.8.0-beta.2
release-1.8.0-beta.3
release-1.8.0-beta.4
release-1.8.1
release-1.8.10
release-1.8.2
release-1.8.3
release-1.8.4
release-1.8.5
release-1.8.6
release-1.8.7
release-1.8.8
release-1.9.0