CVE-2026-54909: Pion STUN vulnerable to remote denial of service via panic while parsing a malformed XOR-MAPPED-ADDRESS attribute

Severity: medium (CVSS 5.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-07-31 · updated 2026-10-23
Weakness: CWE-20

Description

pion/stun is a Go implementation of STUN. Prior to 3.1.3, XORMappedAddress.GetFromAs can panic while parsing a malformed short XOR-MAPPED-ADDRESS attribute in STUN or ICE Binding-response parsing paths, allowing remote denial of service. This issue is fixed in version 3.1.3.

Affected products

pion stun: before 3.1.3

References

https://github.com/pion/stun/commit/fa9f074a33a8059c76c960b1fbee39f308002423
https://github.com/pion/stun/pull/278
https://github.com/pion/stun/releases/tag/v3.1.3
https://github.com/pion/stun/security/advisories/GHSA-34rh-wp3j-6cxc

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