CVE-2026-72466

CVE CVE-2026-72466EUVD EUVD-2026-59365Veröffentlicht 2026-08-15T05:57:09.000ZZuletzt geändert 2026-08-17T05:44:32.000ZCVSS 9.8

Was das Advisory beschreibt

In the Linux kernel, the following vulnerability has been resolved: xprtrdma: Fix bcall rep leak and unbounded peek rpcrdma_is_bcall() decodes a reply's first words to decide whether the frame is a backchannel call. Two issues in that decode path let a short or malformed reply leak the receive buffer and drain the Receive queue. First, the speculative peek p = xdr_inline_decode(xdr, 0); /* five p++ reads follow */ asks xdr_inline_decode() for zero bytes, which returns xdr->p without consulting xdr->end. The five subsequent __be32 reads can then walk up to 20 bytes past the wire payload into stale regbuf contents and misclassify the reply as a backchannel call. Second, after the post-peek p = xdr_inline_decode(xdr, 3 * sizeof(*p)); if (unlikely(!p)) return true; the short-header arm returns true without calling rpcrdma_bc_receive_call(). The contract with the caller is that a true return transfers ownership of rep to the backchannel path: rpcrdma_reply_handler() if (rpcrdma_is_bcall(r_xprt, rep)) return; /* bare return, skips out_post */ ... out_post: rpcrdma_post_recvs(r_xprt, credits + ...); Because rpcrdma_bc_receive_call() never ran, no one took rep, but rpcrdma_reply_handler still bare-returns past rpcrdma_rep_put() and rpcrdma_post_recvs(). The rep, with its persistently DMA-mapped receive buffer, is orphaned on rb_all_reps and freed only at transport teardown. This completion reposts nothing, so its slot is reclaimed only when a later forward-channel reply reaches out_post and rpcrdma_post_recvs() allocates a fresh rep to backfill; absent that traffic the Receive queue drains and the peer's Sends draw RNR NAKs. Fix by consulting xdr->end after the zero-length peek so the five __be32 reads cannot run unless 20 bytes of wire payload remain. A byte-precise comparison against xdr->end is required because a non-4-aligned receive rounds the stream's word count up past the true payload. Also return false from the short-header arm so the reply falls through the normal out_norqst cleanup chain (rpcrdma_rep_put() plus rpcrdma_post_recvs()).

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 4.14; patch: 6.18.40; 41c8f70f5a3db7e06179186b6525fd9ee1d7d314 <7afc2f8d2fd9394724df9eaf22ce7a71029a5fba; patch: 6.1.178; 41c8f70f5a3db7e06179186b6525fd9ee1d7d314 <d7a2870dde3bb09d51d6b9c877642996ad6b92dd; 41c8f70f5a3db7e06179186b6525fd9ee1d7d314 <88b5346284a184a6b7d019912232a571d672d3e3; patch: 6.6.145; patch: 7.2; patch: 0; patch: 6.12.97; 41c8f70f5a3db7e06179186b6525fd9ee1d7d314 <118a16a18c59f7ad8084b2d13988839b669fca10; 41c8f70f5a3db7e06179186b6525fd9ee1d7d314 <07aa506436be7634e381e1e1f6d0efa9efc81ecc; 41c8f70f5a3db7e06179186b6525fd9ee1d7d314 <c7653d5cebc8492c77ec0415b5e9c0fb3e644bc6; patch: 5.15.212; 41c8f70f5a3db7e06179186b6525fd9ee1d7d314 <0cee8f9c3b14bd6dee9c4310090a7f45b89b834f; patch: 7.1.5

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.