undici vulnerable to cross-user cookie disclosure via Set-Cookie caching in shared caches

Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

Severity and exploitation

• CISA KEV Not listed.
• EPSS 0.0030, the 23rd percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

1. 31 Oct 2026, 13:34 UTC Confirmed by OSV

Sources

• GitHub Advisory Database: GHSA-2jfj-6hjv-fm6j
• OSV: GHSA-2jfj-6hjv-fm6j
• github.com/nodejs/undici/security/advisories/GHSA-2jfj-6hjv-fm6j
• nvd.nist.gov/vuln/detail/CVE-2026-84933
• github.com/nodejs/undici/commit/b6c5a00252c37da9dd2db9bead053bb843e1f988
• github.com/nodejs/undici/commit/cb75bbb34224a968b4ad80cab8b7aba5e0b3b28a
• cna.openjsf.org/security-advisories.html
• github.com/nodejs/undici
• github.com/nodejs/undici/releases/tag/v7.29.1
• github.com/nodejs/undici/releases/tag/v8.10.2

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.