CVE-2024-14041

In Bouncy Castle for Java from 1.73 to before 1.78, three ML-KEM (CRYSTALS-Kyber) routines divided secret-derived polynomial coefficients by the modulus q: Poly.toMsg, which decodes the decrypted message, and the ciphertext compression routines Poly.compressPoly and PolyVec.compressPolyVec. An attacker able to measure the timing of a large number of decapsulations performed with the same long-term private key can recover that key. These are the KyberSlash1 (Poly.toMsg) and KyberSlash2 (ciphertext compression) divisions. Compression performed during encapsulation operates on values that become the public ciphertext and is not affected.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/bcgit/bc-java/commit/1590247178f2280defa36421475f015175dfbe9e	Patch
https://github.com/bcgit/bc-java/commit/5adb2c5c5b462a332b01a012bea0784b40b904e5	Patch
https://github.com/bcgit/bc-java/wiki/CVE-2024-14041	Vendor Advisory
https://kyberslash.cr.yp.to/	Exploit

Configurations

Configuration 1 (hide)

cpe:2.3:a:bouncycastle:bc-java:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-07-28 08:17

Updated : 2026-08-26 17:11

NVD link : CVE-2024-14041

Mitre link : CVE-2024-14041

CVE.ORG link : CVE-2024-14041

JSON object : View

Products Affected

bouncycastle

bc-java

CWE

CWE-208

Observable Timing Discrepancy

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