CVE-2024-36405: liboqs — Fix

Description

liboqs is a C-language cryptographic library that provides implementations of post-quantum cryptography algorithms. A control-flow timing lean has been identified in the reference implementation of the Kyber key encapsulation mechanism when it is compiled with Clang 15-18 for `-Os`, `-O1`, and other compilation options. A proof-of-concept local attack on the reference implementation leaks the entire ML-KEM 512 secret key in ~10 minutes using end-to-end decapsulation timing measurements. The issue has been fixed in version 0.10.1. As a possible workaround, some compiler options may produce vectorized code that does not leak secret information, however relying on these compiler options as a workaround may not be reliable.

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CVSS v3.1 Score

5.9

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Weakness Type (CWE)

CWE-208 CWE-208

CWE-385 CWE-385

Affected Products

Vendor	Product	Versions
openquantumsafe	liboqs	< 0.10.1

References

Advisories & Patches

https://github.com/open-quantum-safe/liboqs/commit/982c762c242ef549c914891b47bf6e0ed6321f91 https://github.com/open-quantum-safe/liboqs/security/advisories/GHSA-f2v9-5498-2vpp https://github.com/pq-crystals/kyber/commit/9b8d30698a3e7449aeb34e62339d4176f11e3c6c https://github.com/open-quantum-safe/liboqs/commit/982c762c242ef549c914891b47bf6e0ed6321f91 https://github.com/open-quantum-safe/liboqs/security/advisories/GHSA-f2v9-5498-2vpp https://github.com/pq-crystals/kyber/commit/9b8d30698a3e7449aeb34e62339d4176f11e3c6c

Other References

https://github.com/open-quantum-safe/liboqs/blob/7eecda6095c003ddded7175a1ffdf35a2ce63ed5/src/kem/kyber/pqcrystals-kyber_kyber512_ref/poly.c#L166 https://github.com/open-quantum-safe/liboqs/blob/7eecda6095c003ddded7175a1ffdf35a2ce63ed5/src/kem/kyber/pqcrystals-kyber_kyber512_ref/poly.c#L166

Frequently Asked Questions

What is CVE-2024-36405? +

liboqs is a C-language cryptographic library that provides implementations of post-quantum cryptography algorithms. A control-flow timing lean has been identified in the reference implementation of the Kyber key encapsulation mechanism when it is compiled with Clang 15-18 for `-Os`, `-O1`, and other compilation options. A proof-of-concept local attack on the reference implementation leaks the entire ML-KEM 512 secret key in ~10 minutes using end-to-end decapsulation timing measurements. The issue has been fixed in version 0.10.1. As a possible workaround, some compiler options may produce vectorized code that does not leak secret information, however relying on these compiler options as a workaround may not be reliable. It has a CVSS v3.1 base score of 5.9 (MEDIUM).

How severe is CVE-2024-36405? +

CVE-2024-36405 has a CVSS v3.1 score of 5.9 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2024-36405? +

CVE-2024-36405 affects products from openquantumsafe, specifically: liboqs. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-36405? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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