CIRCL has an incorrect calculation in secp384r1 CombinedMult

CRITICAL 9.8CVE-2026-1229 · GHSA-q9hv-hpm4-hj6x · GO-2026-4550 · Published 24/02/2026 · updated 17/06/2026

Package	Affected versions	Patched versions
github.com/cloudflare/circl Go	`< 1.6.3`	`1.6.3`
circl cloudflare	`< 1.6.3`	`1.6.3`

Description

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.

NVD description

References

cloudflare/circl security advisory · WEB
nvd.nist.gov/vuln/detail/CVE-2026-1229 · ADVISORY
cloudflare/circl#583 · WEB
cloudflare/circl · PACKAGE
cloudflare/circl release v1.6.3 · WEB

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