CVE-2026-44581
mediumpriority · track · 0EPSS 0.002 · 13 %ileDEEURUUSEPSS · scored 2026-10-27
Next.js is a React framework for building full-stack web applications. From 13.4.0 to before 15.5.16 and 16.2.5, App Router applications that rely on CSP nonces can be vulnerable to stored cross-site scripting when deployed behind shared caches. In affected versions, malformed nonce values derived from request headers could be reflected into rendered HTML in an unsafe way, allowing an attacker to poison cached responses and cause script execution for later visitors. This vulnerability is fixed in 15.5.16 and 16.2.5.
cvss
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ssvc
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weaknesses
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affected products (13)
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advisories (2)
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- WID-SEC-W-2026-1401Vercel Next.js: Mehrere SchwachstellenDeutsch2026-05-06csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Vercel Next.js ausnutzen, um Sicherheitsvorkehrungen zu umgehen, Cross-Site-Scripting-Angriffe durchzuführen, Daten zu manipulieren, vertrauliche Informationen offenzulegen oder einen Denial-of-Service-Zustand zu verursachen.
- GHSA-ffhc-5mcf-pf4qNext.js vulnerable to cross-site scripting in App Router applications using CSP nonces2026-05-11ghsa · osvUS
### Impact App Router applications that rely on CSP nonces can be vulnerable to stored cross-site scripting when deployed behind shared caches. In affected versions, malformed nonce values derived from request headers could be reflected into rendered HTML in an unsafe way, allowing an attacker to poison cached responses and cause script execution for later visitors. ### Fix We now reject or ignore malformed nonce values before they are embedded into HTML and apply stricter nonce sanitization so request-derived nonce data cannot break out of the intended attribute context. ### Workarounds If you cannot upgrade immediately, strip inbound `Content-Security-Policy` request headers from untrusted traffic.
also known as (5)
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sources
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references (4)
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