CVE-2026-59640

In Bouncy Castle for Java before 1.85, OpenPGP CFB quick-check oracle active on symmetric/session-key paths. This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bcpg-fips 1.0.13 (1.0.X series), 2.0.13 (2.0.X series) and 2.1.13 (2.1.X series).

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/bcgit/bc-java/commit/6b94b1c146cec1f565d9a85847fae511af77503e	Patch
https://github.com/bcgit/bc-java/wiki/CVE%E2%80%902026%E2%80%9059640	Third Party Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:bouncycastle:bc-java::::::::
	cpe:2.3:a:bouncycastle:bcpg-fips::::::::
	cpe:2.3:a:bouncycastle:bcpg-fips::::::::
	cpe:2.3:a:bouncycastle:bcpg-fips::::::::
	cpe:2.3:a:bouncycastle:bouncy_castle_for_java_lts::::::::

History

No history.

Information

Published : 2026-08-03 01:16

Updated : 2026-08-28 15:40

NVD link : CVE-2026-59640

Mitre link : CVE-2026-59640

CVE.ORG link : CVE-2026-59640

JSON object : View

Products Affected

bouncycastle

bouncy_castle_for_java_lts
bc-java
bcpg-fips

CWE

CWE-203

Observable Discrepancy

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This issue also affects Bouncy Castle for Java LTS before 2.73.12, and Bouncy Castle for Java FIPS (BC-FJA) before bcpg-fips 1.0.13 (1.0.X series), 2.0.13 (2.0.X series) and 2.1.13 (2.1.X series)."}], "lastModified": "2026-08-28T15:40:23.910", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:bouncycastle:bc-java:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "FA6A5663-2E62-44AA-8A64-A3CB0DC8813B", "versionEndExcluding": "1.85"}, {"criteria": "cpe:2.3:a:bouncycastle:bcpg-fips:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "686E3CE8-99E5-46EC-8D70-E4D7B3F3961D", "versionEndExcluding": "1.0.13"}, {"criteria": "cpe:2.3:a:bouncycastle:bcpg-fips:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "0A2E6B4A-1969-427B-B219-3797B414423B", "versionEndExcluding": "2.0.13", "versionStartIncluding": "2.0.8"}, {"criteria": "cpe:2.3:a:bouncycastle:bcpg-fips:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "2B2F95C9-7F17-4670-8691-53E93ED2436E", "versionEndExcluding": "2.1.13", "versionStartIncluding": "2.1.10"}, {"criteria": "cpe:2.3:a:bouncycastle:bouncy_castle_for_java_lts:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F5ED4F42-08FF-4642-815D-1ED0C82FDBD2", "versionEndIncluding": "2.73.11"}], "operator": "OR"}]}], "sourceIdentifier": "91579145-5d7b-4cc5-b925-a0262ff19630"}