symfony/polyfill-intl-idn: xn-- labels with ASCII-only Punycode payloads are treated as equivalent to their decoded form

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 0.0054, the 45th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

1. 31 Oct 2026, 13:59 UTC First seen by agentprime
2. 31 Oct 2026, 13:59 UTC Confirmed by OSV

Sources

• GitHub Advisory Database: GHSA-2xf4-cg6j-vhgq
• OSV: GHSA-2xf4-cg6j-vhgq
• github.com/symfony/polyfill/security/advisories/GHSA-2xf4-cg6j-vhgq
• github.com/symfony/polyfill/commit/1be936e2491ccebe152bd736dfc91eb1422c8bec
• github.com/FriendsOfPHP/security-advisories/blob/master/symfony/polyfill-intl-idn/CVE-2026-46644.yaml
• github.com/FriendsOfPHP/security-advisories/blob/master/symfony/polyfill/CVE-2026-46644.yaml
• github.com/symfony/polyfill
• symfony.com/cve-2026-46644

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.