Observable Discrepancy in libsecp256k1-rs

published 2020-01-22 6y ago modified 2026-06-17 4mo ago also GHSA-7cqg-8449-rmfv , RUSTSEC-2020-0156 , EUVD-2021-1618

cvss: 5.9; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.9%; EPSS 0.9% chance of exploitation in 30 days, percentile 59%
public exploits: 0; none known

A timing vulnerability in the Scalar::check_overflow function in Parity libsecp256k1-rs before 0.3.1 potentially allows an attacker to leak information via a side-channel attack.

Patch / fix

fixed in 2 links 1

crates.io libsecp256k1-rs 0.3.1
parity libsecp256k1 0.3.1

github.com/paritytech/libsecp256k1@11ba23a commit

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Exploit prediction

0.88% chance of exploitation in the next 30 days, higher than 59% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.1	5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
NVD	2.0	4.3	AV:N/AC:M/Au:N/C:P/I:N/A:N
GitHub	3.1	5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
OSV	3.1	5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Affected packages

ecosystem	package	affected	fixed in
crates.io	libsecp256k1-rs	<0.3.1 >=0.0.0-0, <0.3.1	0.3.1

Classification

Weakness

CWE-203 Observable Discrepancy
CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization

References

github.com /paritytech/libsecp256k1/commit/11ba23a9766a5079918cd9f515bc100bc8164b50
web, patch, third-party-advisory
nvd.nist.gov /vuln/detail/CVE-2019-20399
advisory, web
rustsec.org /advisories/RUSTSEC-2020-0156.html
web, advisory
crates.io /crates/libsecp256k1-rs
package

Sources

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