Description
In the Linux kernel, the following vulnerability has been resolved: scsi: libiscsi: Reject a negative task index from parse_pdu_itt A transport that implements parse_pdu_itt hands libiscsi an index taken from the PDU, and both lookups bound it from above only: if (i >= session->cmds_max) i and cmds_max are both int, so a negative index passes and session->cmds[i] is read from before the array. be2iscsi produces one. beiscsi_parse_pdu() assigns the raw tag, *index = (int)itt; and beiscsi_complete_pdu() forwards an unsolicited NOP-In from the hardware async ring without replacing its ITT, so the value is the target's. It also reports the session's own age rather than the one in the tag, which leaves the age comparison in iscsi_verify_itt() with nothing to reject. Bound the index from below in both lookups.
References8
- git.kernel.org/stable/c/0eb06ebbbecb122f0df9a1f7f623f5255be741ed
- git.kernel.org/stable/c/24bd9ba431b2daa263f3551bc2f09f6b4487f5ae
- git.kernel.org/stable/c/35b60549a956237488c89a2d85352e026e7d55b7
- git.kernel.org/stable/c/6200fb2de579f268742a77b0f3d823cb0a8b1947
- git.kernel.org/stable/c/6cadfa6f1f5896632d4223d3b7addb2a29fea74e
- git.kernel.org/stable/c/8ee2a09a1dbb257c9e828ad2497f8e4832dfb142
- git.kernel.org/stable/c/e896a97f336c5edfc13066b57ed431cb3f64e68c
- git.kernel.org/stable/c/f8fabe1fe044f86abc42194b8f86dfd70212115f
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 44 · as of 3 November 2026
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