Exponential ReDoS in semver-regex

published 2022-06-01 4 y ago modified 2026-09-10 1 mo ago also GHSA-4x5v-gmq8-25ch , EUVD-2022-5926

cvss: 5.9; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.6%; EPSS 1.6% chance of exploitation in 30 days, percentile 75%
public exploits: 0; none known

An exponential ReDoS (Regular Expression Denial of Service) can be triggered in the semver-regex npm package, when an attacker is able to supply arbitrary input to the test() method

Patch / fix

fixed in 2 links 1

npm semver-regex 3.1.4, 4.0.3
semver-regex semver-regex 3.1.4, 4.0.3

github.com/sindresorhus/semver-regex@d8ba39a commit

Exploit prediction

1.56% chance of exploitation in the next 30 days, higher than 75% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

research.jfrog.com https://research.jfrog.com/vulnerabilities/semver-regex-redos-xray-211349/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.9	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	3.1	7.5	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:N/A:P

Affected packages

ecosystem	package	affected	fixed in
npm	semver-regex	<3.1.4 >=4.0.0, <4.0.3	3.1.4 4.0.3

Affected products

semver-regex semver-regex

Classification

Weakness

CWE-1333 Inefficient Regular Expression Complexity

References

github.com /sindresorhus/semver-regex/commit/d8ba39a528c1027c43ab23f12eec28ca4d40dd0c
web
research.jfrog.com /vulnerabilities/semver-regex-redos-xray-211349/
exploit, third-party-advisory
nvd.nist.gov /vuln/detail/CVE-2021-43307
advisory
github.com /sindresorhus/semver-regex
package
research.jfrog.com /vulnerabilities/semver-regex-redos-xray-211349
web

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