CVE-2026-46644

Symfony Polyfill backports PHP features and provides compatibility layers for extensions and functions. From 1.17.1 until 1.38.1, symfony/polyfill-intl-idn accepts xn-- labels whose Punycode payload is empty or decodes to ASCII-only code points because Idn::process() does not enforce the UTS #46 revision 33 requirement that decoded ACE labels contain at least one non-ASCII code point. Originally unequal domain names can be regarded as equal, which can lead to blacklist bypassing, inconsistent URL parsing, and server-side request forgery in applications using the polyfill to canonicalise or compare hostnames. This issue is fixed in version 1.38.1.

CVSS

No CVSS.

References

Link	Resource
https://github.com/symfony/polyfill/commit/1be936e2491ccebe152bd736dfc91eb1422c8bec
https://github.com/symfony/polyfill/releases/tag/v1.38.1
https://github.com/symfony/polyfill/security/advisories/GHSA-2xf4-cg6j-vhgq

Configurations

No configuration.

History

14 Jul 2026, 21:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-14 21:16

Updated : 2026-07-15 18:16

NVD link : CVE-2026-46644

Mitre link : CVE-2026-46644

CVE.ORG link : CVE-2026-46644

JSON object : View

Products Affected

No product.

CWE

CWE-1289

Improper Validation of Unsafe Equivalence in Input

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