CVE-2026-44582: vercel next.js Use of Weak Hash

Vulnerability summary

CVE-2026-44582 is a low (CVSS 3.7) Use of Weak Hash vulnerability in vercel next.js. EPSS estimates a 0.17% chance of exploitation in the next 30 days, higher than 6.1% of scored vulnerabilities.

Timeline

1. 13-05-2026
   PublishedVulnerability first disclosed.
2. 14-05-2026
   Last modifiedVulnerability information updated.

Description

Next.js is a React framework for building full-stack web applications. From 13.4.6 to before 15.5.16 and 16.2.5, React Server Component responses can be vulnerable to cache poisoning in deployments that rely on shared caches with insufficient response partitioning. In affected conditions, collisions in the _rsc cache-busting value can allow an attacker to poison cache entries so users receive the wrong response variant for a given URL. This vulnerability is fixed in 15.5.16 and 16.2.5.

• CWE-328Use of Weak HashThe product uses an algorithm that produces a digest (output value) that does not meet security expectations for a hash function that allows an adversary to reasonably determine the original input (preimage attack), find another input that can produce the same hash (2nd preimage attack), or find multiple inputs that evaluate to the same hash (birthday attack).