CVE-2026-80784

CVE CVE-2026-80784EUVD EUVD-2026-71427Veröffentlicht 2026-09-04T15:12:56.000Z

Was das Advisory beschreibt

In the Linux kernel, the following vulnerability has been resolved: mptcp: pm: fix memory leak from alloc-during-teardown race mptcp_pm_destroy() empties msk->pm.anno_list and msk->pm.userspace_pm_local_addr_list under msk->pm.lock during socket teardown, dropping the lock between the two. A concurrent userspace PM genl ANNOUNCE on the same msk holds a sock reference via mptcp_token_get_sock() and, in mptcp_pm_nl_announce_doit(), calls mptcp_userspace_pm_append_new_local_addr() and mptcp_pm_announced_alloc(). Both take msk->pm.lock briefly to add to their respective lists. Because the genl handler holds a sock reference, mptcp_pm_destroy() may run on the same msk via mptcp_disconnect(), which invokes mptcp_destroy_common() without dropping the sock refcount, before the handler completes. If the lock acquisitions interleave such that mptcp_pm_destroy() empties a list first, the later alloc adds its entry to a list head that nothing else iterates for this msk, and the entry leaks. kmemleak reports both mptcp_pm_add_addr objects (from mptcp_pm_announced_alloc()) and mptcp_pm_addr_entry objects (from mptcp_userspace_pm_append_new_local_addr()) under sustained concurrent ANNOUNCE + close load against the userspace PM. Add an MPTCP_PM_DESTROYING bit in msk->pm.status, set by mptcp_pm_destroy() under pm.lock before the lists are emptied and checked under pm.lock by the alloc paths. Either the alloc takes pm.lock first, in which case its entry is on the list when mptcp_pm_destroy() frees it; or mptcp_pm_destroy() takes pm.lock first, in which case the later alloc observes the bit and refuses. Found by an MPTCP protocol-flow harness extending BRF (arXiv:2305.08782).

Quelle: EUVD (ENISA), im Wortlaut der Meldung.

Produkte, die das Advisory nennt

Diese Angaben stammen aus der Meldung selbst, nicht aus einer Prüfung durch uns.

• Linux — Linux 9ab4807c84a4aacfc9b4f79cc81254035e0ec361 <f48341830e4202db3fe884b819b2db6740f0537d; 9ab4807c84a4aacfc9b4f79cc81254035e0ec361 <bb32e9a6a9a9f99eeda16c4efe443400f3e43892; patch: 6.1.187; 9ab4807c84a4aacfc9b4f79cc81254035e0ec361 <9fe5eebb664ecdba88f3fde18062d94b1d1c465f; patch: 7.2; patch: 7.1.11; 5.19; 9ab4807c84a4aacfc9b4f79cc81254035e0ec361 <b2a0b55bf613bd3e81ed26a847b0f6b8e6b7f804; patch: 6.18.47; patch: 0; 9ab4807c84a4aacfc9b4f79cc81254035e0ec361 <6c290915a03fc8228b473641025cf762b256dbd2; 9ab4807c84a4aacfc9b4f79cc81254035e0ec361 <efc33b5102ff859bacd390a5f30112d8e0c084c0; patch: 6.12.106; patch: 6.6.154

Die genannten Versionen sind die Angabe der Meldung. Patchlage vergleicht keine Versionsnummern und leitet aus ihnen keine Aussage ab — welche Version installiert ist, muss ein Mensch nachsehen.

Im Produktkatalog geführt

Für diese Produkte kann ein Bestand in Patchlage erfasst werden. Ein Advisory dazu erscheint am Morgen danach im Lagebericht.

• Linux — Linux

Patchlage meldet Treffer und Verdachtsfälle. Zu allem anderen sagt dieses System nichts — weder diese Seite noch der Lagebericht behauptet je, dass ein Bestand sicher ist.