Regular Expression Denial of Service in negotiator

HIGH 7.5CVE-2016-10539 · GHSA-7mc5-chhp-fmc3 · Published 31/05/2018 · updated 17/06/2026

In short

CVE-2016-10539 is a HIGH (CVSS 7.5) vulnerability affecting negotiator (negotiator project), negotiator.
Chance of exploitation in the next 30 days (EPSS): 1.4%, higher than 72.5% of all vulnerabilities.
Fix: update to 0.6.1 or later.

Package	Affected versions	Patched versions
negotiator negotiator_project	`≤ 0.6.0`	No fix yet
negotiator npm	`< 0.6.1`	`0.6.1`

Description

Affected versions of negotiator are vulnerable to regular expression denial of service attacks, which trigger upon parsing a specially crafted Accept-Language header value.

Recommendation

Update to version 0.6.1 or later.

NVD description

negotiator is an HTTP content negotiator for Node.js and is used by many modules and frameworks including Express and Koa. The header for "Accept-Language", when parsed by negotiator 0.6.0 and earlier is vulnerable to Regular Expression Denial of Service via a specially crafted string.

References

nvd.nist.gov/vuln/detail/CVE-2016-10539 · ADVISORY
GitHub Advisory GHSA-7mc5-chhp-fmc3 · ADVISORY
npmjs.com/advisories/106 · WEB
nodesecurity.io/advisories/106 · Third Party Advisory

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