CVE-2026-1229 PUBLISHED

Incorrect calculation in CIRCL secp384r1 CombinedMult

Assigner: cloudflare
Reserved: 20.01.2026 Published: 24.02.2026 Updated: 24.02.2026

The CombinedMult function in the CIRCL ecc/p384 package (secp384r1 curve) produces an incorrect value for specific inputs. The issue is fixed by using complete addition formulas. ECDH and ECDSA signing relying on this curve are not affected.

The bug was fixed in v1.6.3 https://github.com/cloudflare/circl/releases/tag/v1.6.3 .

Metrics

CVSS 4.0

CVSS Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L/E:P/S:N/AU:Y/U:Amber
CVSS Score: 2.9

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	Low	Confidentiality	Low
Attack Complexity	High	Integrity	Low	Integrity	Low
Attack Requirements	None	Availability	Low	Availability	Low
Privileges Required	None
User Interaction	None

CVSS 4.0

Product Status

Vendor	Cloudflare
Product	CIRCL
Versions	Default: unaffected affected from CIRCL up to version 1.6.2 to 1.6.3 (excl.)

Credits

Guido Vranken finder

References

https://github.com/cloudflare/circl

Problem Types

CWE-682 Incorrect Calculation CWE