CVE-2026-84933Medium· 6.5▾ Sunlitundici's cache interceptor does not handle the Set-Cookie response header anywhere in its cache path, so it neither refuses to store nor strips that header. In shared cache mode, which is the default, an otherwise cacheable response that…
▾ Sunlit zone — Low / medium · no exploitation signal
impact 35.8 · likelihood 0.1 · exploitation 0
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Exploit-prediction probability, daily snapshots since Sep 8.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via NVD
0.2%
Last analysed / modified upstream
0.2% → 0.3%
undici's cache interceptor does not handle the Set-Cookie response header anywhere in its cache path, so it neither refuses to store nor strips that header. In shared cache mode, which is the default, an otherwise cacheable response that carries a Set-Cookie header, for example one marked with a public and max-age directive, is stored and then re-served to a later caller that matches the same cache key. As a result one caller's cookie is disclosed to a different caller, and an untrusted server can inject cookies into cached responses served to all subsequent callers. This violates the requirement that a shared cache must not store cookies. This affects undici versions from 7.0.0 up to 7.29.1 and from 8.0.0 up to 8.10.2. Users should upgrade to undici 7.29.1 or 8.10.2.
undici >= 7.0.0, < 7.29.1undici >= 8.0.0, < 8.10.2Upgrade past the affected range:
undici 8.10.2Affected packages:
undici >= 7.0.0, < 7.29.1undici >= 8.0.0, < 8.10.2Patched in:
undici 7.29.1undici 8.10.2Connected by shared product, vendor, weakness, or advisory.
CVE-2026-84890Medium· 5.9undici's decompress interceptor decompresses response bodies according to the untrusted Content-Encoding header
CVE-2026-18149Medium· 5.9undici's retry handler can leave an already-exposed response body pending forever
CVE-2026-18540Low· 3.7undici's retry interceptor can append the body of a ranged retry response to bytes already delivered from an earlier partial response while still presenting the original response's status and headers
CVE-2026-19534High· 7.5undici's WebSocket client crashes the whole Node.js process during the opening handshake when a server responds with a subprotocol that the client never requested
CVE-2026-84947Low· 3.7undici's dump interceptor reads and discards a response body up to a configurable maximum size
CVE-2026-84961High· 7.4undici's BalancedPool constructor passes its entire options object through an internal deep-clone that serializes and reparses the value as JSON