EUVD-2026-15289
Lifecycle Timeline
4Description
In the Linux kernel, the following vulnerability has been resolved: udp: Unhash auto-bound connected sk from 4-tuple hash table when disconnected. Let's say we bind() an UDP socket to the wildcard address with a non-zero port, connect() it to an address, and disconnect it from the address. bind() sets SOCK_BINDPORT_LOCK on sk->sk_userlocks (but not SOCK_BINDADDR_LOCK), and connect() calls udp_lib_hash4() to put the socket into the 4-tuple hash table. Then, __udp_disconnect() calls sk->sk_prot->rehash(sk). It computes a new hash based on the wildcard address and moves the socket to a new slot in the 4-tuple hash table, leaving a garbage in the chain that no packet hits. Let's remove such a socket from 4-tuple hash table when disconnected. Note that udp_sk(sk)->udp_portaddr_hash needs to be udpated after udp_hash4_dec(hslot2) in udp_unhash4().
Analysis
A resource management vulnerability in the Linux kernel UDP implementation causes improper handling of socket state during disconnect operations. When a UDP socket is bound to a wildcard address, connected to a remote peer, and then disconnected, the kernel fails to properly remove the socket from the 4-tuple hash table, leaving stale entries that can lead to information disclosure or denial of service conditions. …
Sign in for full analysis, threat intelligence, and remediation guidance.
Priority Score
Vendor Status
Debian
| Release | Status | Fixed Version | Urgency |
|---|---|---|---|
| bullseye | not-affected | - | - |
| bullseye (security) | fixed | 5.10.251-1 | - |
| bookworm | not-affected | - | - |
| bookworm (security) | fixed | 6.1.164-1 | - |
| trixie | not-affected | - | - |
| trixie (security) | fixed | 6.12.74-2 | - |
| forky, sid | fixed | 6.19.8-1 | - |
| (unstable) | fixed | 6.19.8-1 | - |
Share
External POC / Exploit Code
Leaving vuln.today