Improper Validation of Unsafe Equivalence in Input Affecting php-symfony-polyfill package, versions <1.38.1-1
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-DEBIAN14-PHPSYMFONYPOLYFILL-17082614
- published29 May 2026
- disclosed14 Jul 2026
Introduced: 29 May 2026
CVE-2026-46644 (opens in a new tab)How to fix?
Upgrade Debian:14 php-symfony-polyfill to version 1.38.1-1 or higher.
NVD Description
Note: Versions mentioned in the description apply only to the upstream php-symfony-polyfill package and not the php-symfony-polyfill package as distributed by Debian.
See How to fix? for Debian:14 relevant fixed versions and status.
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.