Improper Validation of Unsafe Equivalence in Input Affecting frankenphp-8.3 package, versions <1.12.2-r0


Severity

Recommended
low

Based on default assessment until relevant scores are available.

Threat Intelligence

Social Trends
EPSS
0.34% (26th percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-FRANKENPHP83-16004223
  • published13 Apr 2026
  • disclosed9 Apr 2026

Introduced: 9 Apr 2026

CVE-2026-39972  (opens in a new tab)
CWE-1289  (opens in a new tab)

How to fix?

Upgrade Chainguard frankenphp-8.3 to version 1.12.2-r0 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream frankenphp-8.3 package and not the frankenphp-8.3 package as distributed by Chainguard. See How to fix? for Chainguard relevant fixed versions and status.

Mercure is a protocol for pushing data updates to web browsers and other HTTP clients in a battery-efficient way. Prior to 0.22.0, a cache key collision vulnerability in TopicSelectorStore allows an attacker to poison the match result cache, potentially causing private updates to be delivered to unauthorized subscribers or blocking delivery to authorized ones. The cache key was constructed by concatenating the topic selector and topic with an underscore separator. Because both topic selectors and topics can contain underscores, two distinct pairs can produce the same key. An attacker who can subscribe to the hub or publish updates with crafted topic names can exploit this to bypass authorization checks on private updates. This vulnerability is fixed in 0.22.0.