CVE-2026-72135

CVE CVE-2026-72135EUVD EUVD-2026-58893Veröffentlicht 2026-08-15T05:53:10.000ZZuletzt geändert 2026-08-17T05:40:45.000ZCVSS 7.8

Was das Advisory beschreibt

In the Linux kernel, the following vulnerability has been resolved: tpm: Make the TPM character devices non-seekable The TPM character devices expose a sequential command/response interface, but their open handlers leave FMODE_PREAD and FMODE_PWRITE enabled. After a command leaves a response pending, pread(fd, buf, 16, 0x1400) passes 0x1400 as *off to tpm_common_read(). The transfer length is bounded by response_length, but the offset is used unchecked when forming data_buffer + *off. A sufficiently large offset therefore causes an out-of-bounds heap read through copy_to_user() and, if the copy succeeds, an out-of-bounds zero-write through the following memset(). Positional I/O does not provide coherent semantics for this interface. An arbitrary pread offset cannot represent how much of a response has been consumed sequentially. The write callback always stores a command at the start of data_buffer, while pwrite() does not update file->f_pos and can leave the sequential read cursor stale. Call nonseekable_open() from both open handlers. This removes FMODE_PREAD and FMODE_PWRITE, causing positional reads and writes to fail with -ESPIPE before reaching the TPM callbacks, and explicitly marks the files non-seekable. Normal read() and write() continue to use the existing sequential f_pos cursor, leaving the response state machine unchanged. Tested on Linux 6.12 with KASAN and a swtpm TPM2 device: - sequential partial reads returned the complete response - pread() and preadv() with offset 0x1400 returned -ESPIPE - pwrite() and pwritev() with offset zero returned -ESPIPE - the pending response remained intact after the rejected operations - a subsequent normal command/response cycle completed normally - no KASAN report was produced.

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 patch: 6.18.40; patch: 6.1.178; 9488585b21bef0df1217e510c7134905d1d376a7 <9c513dabd4540f811585a2087f23069767a284da; patch: 7.1.5; patch: 0; 9488585b21bef0df1217e510c7134905d1d376a7 <ada4b9a5087ea7f30dd8e4c6411a4fb6547eb1ed; 9488585b21bef0df1217e510c7134905d1d376a7 <dda695fab5e21f923d29e8cb01df256468ddfbd1; 5.0; patch: 5.15.212; patch: 6.12.97; 9488585b21bef0df1217e510c7134905d1d376a7 <ed0ffc2c016629e40ba041ed0424a772d8b02e2c; patch: 6.6.145; 9488585b21bef0df1217e510c7134905d1d376a7 <21a13f932972bc9836f58c44fcd47c62abdecd95; patch: 7.2; patch: 5.10.261; 9488585b21bef0df1217e510c7134905d1d376a7 <947b773caaa548672184df025271b29bdc80b0f1; 9488585b21bef0df1217e510c7134905d1d376a7 <f20d61c22bcaf172d6790b6500e3838e532e71c8; 9488585b21bef0df1217e510c7134905d1d376a7 <232dcf908eb7eb9d8046a9597975caf44270966e

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.