Security Vulnerabilities
undici's cache interceptor documents that only safe HTTP methods are cached, but its logic to skip caching is built by subtracting the configured methods from the set of safe methods, so an unsafe method such as POST, PUT, or DELETE is never placed in the skip list and instead falls through to the full cache-read path. The response-storage gate also lacked a method check, so a response to an unsafe request that is heuristically cacheable or carries an explicit Cache-Control directive is stored and later replayed from cache. Because response headers from a remote origin are untrusted, an origin can answer once with a cacheable status and then have the client's own subsequent state-changing requests to that path served from the stale cache entry without ever reaching the origin, an integrity failure that occurs under the interceptor's default configuration. 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.
CVSS Score
3.7
EPSS Score
0.001
Published
2026-09-04
undici's experimental WebSocketStream client crashes the whole Node.js process when a remote peer closes the TCP connection without a WebSocket close handshake. On an unclean close the internal socket-close handler calls abort on the writable stream unconditionally and discards the returned promise, but per the WHATWG Streams standard aborting a locked writable returns a promise that rejects with a TypeError. Because the application holds a writer on that writable, which is the only way to write, the rejection is never observed and Node's default unhandled-rejection behavior terminates the process. An untrusted server can therefore crash a client with a single abrupt disconnect, with no authentication and no application mistake. 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.
CVSS Score
5.9
EPSS Score
0.004
Published
2026-09-04
undici bundles a WebSocket client whose permessage-deflate size-limit cleanup removes all listeners from the internal zlib inflate stream, including its error listener, while that stream can still emit. When a remote peer sends a compressed payload that crosses the built-in 128 MiB decompressed-payload limit and then contains a malformed DEFLATE byte, the inflate stream emits a data error with no listener attached, which Node.js treats as a fatal unhandled error and terminates the entire process. Exploitation is remote and unauthenticated, requires no application mistake, and is asymmetric, since roughly 130 KB on the wire expands past the limit and crashes the process, and reconnecting can repeat the crash. This affects undici versions from 6.25.0 up to 6.28.1, from 7.28.0 up to 7.29.1, and from 8.1.0 up to 8.10.2. Users should upgrade to undici 6.28.1, 7.29.1, or 8.10.2.
CVSS Score
5.9
EPSS Score
0.003
Published
2026-09-04
undici 8.10.0 omits the destination origin from the cache and request-deduplication keys when the cache or deduplicate interceptor is composed directly onto a Client or Pool. Because the internal cache key falls back to an empty origin string, a cacheable or in-flight response from one upstream origin is returned for a request to a different, trusted origin whenever the method, path, and relevant headers match, which permits cross-origin information disclosure and persistent cache poisoning. The reporter demonstrated a full authentication bypass in which a JWT signed with an attacker-controlled key was accepted as belonging to a trusted issuer, and the trusted origin was never contacted. This is a regression introduced in 8.10.0 and affects undici versions from 8.10.0 up to 8.10.2. Applications using an Agent, which carries the origin in its dispatch options, are not affected. Users should upgrade to undici 8.10.2.
CVSS Score
7.4
EPSS Score
0.002
Published
2026-09-04
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.
CVSS Score
6.5
EPSS Score
0.002
Published
2026-09-04
IBM i 7.6, 7.5, 7.4, and 7.3 could allow a remote attacker to manipulate database transactions due to improper authorization in the DDM target dispatcher.
CVSS Score
8.1
EPSS Score
0.002
Published
2026-09-04
IBM i 7.6, 7.5, 7.4, and 7.3 could allow a remote attacker to gain unauthorized access due to improper validation of client-supplied authentication parameters.
CVSS Score
8.1
EPSS Score
0.003
Published
2026-09-04
IBM i 7.6, 7.5, 7.4, and 7.3 could allow a remote authenticated attacker to corrupt memory due to an integer underflow.
CVSS Score
6.3
EPSS Score
0.002
Published
2026-09-04
IBM ContextForge MCP Gateway <= v1.0.7 MCP Context Forge could allow a remote authenticated attacker to obtain sensitive credentials and escalate privileges due to improper validation of jq filters.
CVSS Score
8.8
EPSS Score
0.003
Published
2026-09-04
IBM ContextForge MCP Gateway - Translate utility <= 1.0.8 MCP Context Forge could allow a remote attacker to obtain sensitive information from other sessions due to exposure of data elements to the wrong session.
CVSS Score
7.4
EPSS Score
0.003
Published
2026-09-04