CyberSecBulletin
CVE-2026-72084NVD status: Received

Linux: Out-of-bounds Read

Published Updated By the CyberSecBulletin desk

CVE-2026-72084 is a critical-severity out-of-bounds read vulnerability in Linux, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 88c67c3de914e19172e1d878a7625c5b06c20ec5, 842248047ef28dbf3b3f7f49a0ec315054d4dab8, 03fbc7de8d5e85fc8420e57e8304c855efd453ab as the first without the flaw, so updating Linux to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.74% chance of exploitation within 30 days, higher than 55% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update Linux to 88c67c3de914e19172e1d878a7625c5b06c20ec5 or 842248047ef28dbf3b3f7f49a0ec315054d4dab8 or 03fbc7de8d5e85fc8420e57e8304c855efd453ab or 6ca5de8782e67573a61a6736b6dc0ffe58dcdf59, whichever matches your release line, or a later version.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinuxc66ac9db8d4ad9994a02b3e933ea2ccc643e1fe5 up to, but not including, 88c67c3de914e19172e1d878a7625c5b06c20ec5; c66ac9db8d4ad9994a02b3e933ea2ccc643e1fe5 up to, but not including, 842248047ef28dbf3b3f7f49a0ec315054d4dab8; c66ac9db8d4ad9994a02b3e933ea2ccc643e1fe5 up to, but not including, 03fbc7de8d5e85fc8420e57e8304c855efd453ab; c66ac9db8d4ad9994a02b3e933ea2ccc643e1fe5 up to, but not including, 6ca5de8782e67573a61a6736b6dc0ffe58dcdf59; c66ac9db8d4ad9994a02b3e933ea2ccc643e1fe5 up to, but not including, 9298078a8f7d8181a04614a34ab655ccdf038204; c66ac9db8d4ad9994a02b3e933ea2ccc643e1fe5 up to, but not including, 004ccd2d3b4ac36a300e05e01df152e5c02a5a82; c66ac9db8d4ad9994a02b3e933ea2ccc643e1fe5 up to, but not including, 555a89846ed888d7401b3f7200934c0fbedcbb46; c66ac9db8d4ad9994a02b3e933ea2ccc643e1fe5 up to, but not including, d04a179085c262c9ed577d0a4cbc6482ff1fd9a3; and 1 more ranges88c67c3de914e19172e1d878a7625c5b06c20ec5, 842248047ef28dbf3b3f7f49a0ec315054d4dab8, 03fbc7de8d5e85fc8420e57e8304c855efd453ab, 6ca5de8782e67573a61a6736b6dc0ffe58dcdf59, 9298078a8f7d8181a04614a34ab655ccdf038204, 004ccd2d3b4ac36a300e05e01df152e5c02a5a82

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA.

Official description

In the Linux kernel, the following vulnerability has been resolved: scsi: target: Bound PR-OUT TransportID parsing to the received buffer core_scsi3_decode_spec_i_port() and core_scsi3_emulate_register_and_move() hand the raw PERSISTENT RESERVE OUT parameter buffer to target_parse_pr_out_transport_id() without telling it how many bytes are valid. For an iSCSI TransportID (FORMAT CODE 01b), iscsi_parse_pr_out_transport_id() locates the ",i,0x" ISID separator with an unbounded strstr() (and on the error path prints the name with a further unbounded "%s"). An initiator can submit a TransportID whose iSCSI name contains neither a ",i,0x" substring nor a NUL terminator, filling the parameter list to its end, so the scan runs off the end of the buffer. When the parameter list spans more than one page the buffer is a multi-page vmap (transport_kmap_data_sg()), so the over-read walks into the trailing vmalloc guard page and oopses (KASAN: vmalloc-out-of-bounds in strstr). It is reachable by any fabric that delivers a PR OUT to a device exported through an iSCSI TPG, including a guest via vhost-scsi. Pass the number of received bytes down to the parser and validate the iSCSI TransportID's own self-described length (ADDITIONAL LENGTH + 4) once, up front: reject it if it is below the spc4r17 minimum or larger than the received buffer, then bound the separator search, the ISID walk and the name copy by that length. This is the length check the callers already perform after the parse (core_scsi3_decode_spec_i_port() compares tid_len against tpdl, core_scsi3_emulate_register_and_move() validates it against data_length), moved ahead of the scan. Also drop the unbounded "%s" of the unterminated name. Add per-format explicit name-length checks before copying into i_str, rather than silently truncating with min_t: for FORMAT CODE 00b reject if the descriptor body (tid_len - 4 bytes) cannot fit in i_str[TRANSPORT_IQN_LEN]; for FORMAT CODE 01b reject if the name portion (from &buf[4] up to the separator) cannot fit. Both checks make the bounds intent explicit at each format branch. While here, also reject a FORMAT CODE 01b TransportID whose ",i,0x" separator sits at the very end of the descriptor: that leaves an empty ISID and points the returned port nexus pointer at buf + tid_len, one past the descriptor, which the registration code (__core_scsi3_locate_pr_reg(), __core_scsi3_alloc_registration()) then dereferences as the ISID string -- the same over-read of the parameter buffer for a malformed descriptor.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Out-of-bounds Read

The product reads data past the end, or before the beginning, of the intended buffer.

How developers prevent this class of flaw

  • Use a language that provides appropriate memory abstractions.

More Out-of-bounds Read vulnerabilities (CWE-125)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Out-of-bounds Read vulnerabilities

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