CVE-2026-53349 netfilter: nf_conntrack: destroy stale expectfn expectations on unregister

In the Linux kernel, the following vulnerability has been resolved: netfilter: nfconntrack: destroy stale expectfn expectations on unregister NAT helpers such as nfnath323 store a raw pointer to module text in exp-expectfn e.g. ipnatq931expect. nfcthelperexpectfnunregister only unlinks the callba...

CVE-2026-53349

CVE-2026-53349 affects Linux kernels where netfilter nf_conntrack may call a broken nf_ct_helper_expectfn_unregister path that leaves a dangling exp->expectfn when a NAT helper is removed (e.g., nf_nat_h323). Reproductions show a stale function pointer is invoked on a subsequent connection, po...