Incorrect multiplication of unreduced P-256 scalars in filippo.io/nistec

published 2023-02-28 3 y ago modified 2026-06-17 4 mo ago also GHSA-f6hc-9g49-xmx7 , GO-2023-1595 , EUVD-2023-0995

cvss: 7.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.7%; EPSS 0.7% chance of exploitation in 30 days, percentile 52%
public exploits: 0; none known

Multiplication of certain unreduced P-256 scalars produce incorrect results. There are no protocols known at this time that can be attacked due to this.

Patch / fix

fixed in 2 links 2

go filippo.io/nistec 0.0.2
filippo.io/nistec filippo.io/nistec 0.0.2

github.com/FiloSottile/nistec@c58aa12 commit
go.dev/issue/58647 patch

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 20 mo ago (2025-02-28)

Exploit prediction

0.67% chance of exploitation in the next 30 days, higher than 52% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
CNA	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
GitHub	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Affected packages

ecosystem	package	affected	fixed in
go	filippo.io/nistec	<0.0.2	0.0.2

Affected products

filippo.io/nistec filippo.io/nistec

Classification

Weakness

CWE-682 Incorrect Calculation

References

github.com /FiloSottile/nistec/commit/c58aa1223ccf3943513e1e661cebce95af137244
web, patch
go.dev /issue/58647
web, issue-tracking, patch, report
pkg.go.dev /vuln/GO-2023-1595
web, third-party-advisory
nvd.nist.gov /vuln/detail/CVE-2023-24533
advisory
github.com /FiloSottile/nistec
package

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary