CVE-2026-44582 | Next.js: Cache poisoning via collisions in React Server Component cache-busting

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.

Published: 2026-05-13 Last update: 2026-05-14 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-44582 is rated Low Risk (18.6/100): CVSS Low severity, with low exploitation likelihood (EPSS 0.20%). Low composite risk—no urgent action required; patch on your normal maintenance cycle and revisit priority if CVSS or EPSS increases.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-44582

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.02% 0.20% +0.18%
2 2026-05-14 — 0.02% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-44582

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
3.7 3.1 LOW
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 2.2 1.4 [email protected]

Weakness enumeration for CVE-2026-44582

GitHub Security Advisory for CVE-2026-44582

GHSA-vfv6-92ff-j949 · Severity: low · Ecosystem: npm — Next.js vulnerable to cache poisoning via collisions in React Server Component cache-busting

Affected software / configurations for CVE-2026-44582

Vendor Product Version Raw CPE
vercel next.js >= 13.4.6, < 15.5.16 cpe:2.3:a:vercel:next.js:*:*:*:*:*:node.js:*:*
vercel next.js >= 16.0.0, < 16.2.5 cpe:2.3:a:vercel:next.js:*:*:*:*:*:node.js:*:*

References for CVE-2026-44582

cvelogic Threat Intelligence