CyberSecBulletin
CVE-2026-68131NVD status: Received

In the Linux kernel, the following vulnerability has been resolved: rbd: Reset positive result…

Published Updated By the CyberSecBulletin desk

CVE-2026-68131 is a high-severity improper input validation vulnerability in Linux, with a CVSS 3.1 base score of 7.5 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 cf1167292f606deaddac35ec384eba48f08a68d2, da926959bf791441ba06a80571708c3d0d3cc08f, 6f33d9d539fb94e5a17589c2dfe271ff9bb64904 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 0.52% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Linux to cf1167292f606deaddac35ec384eba48f08a68d2 or da926959bf791441ba06a80571708c3d0d3cc08f or 6f33d9d539fb94e5a17589c2dfe271ff9bb64904 or 14995c4250f04b58bf6fc00e0e973a2e1b3cfb9b, 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
LinuxLinux22e8bd51bb0469d1a524130a057f894ff632376a up to, but not including, cf1167292f606deaddac35ec384eba48f08a68d2; 22e8bd51bb0469d1a524130a057f894ff632376a up to, but not including, da926959bf791441ba06a80571708c3d0d3cc08f; 22e8bd51bb0469d1a524130a057f894ff632376a up to, but not including, 6f33d9d539fb94e5a17589c2dfe271ff9bb64904; 22e8bd51bb0469d1a524130a057f894ff632376a up to, but not including, 14995c4250f04b58bf6fc00e0e973a2e1b3cfb9b; 22e8bd51bb0469d1a524130a057f894ff632376a up to, but not including, 2419aa74081007dc4d14ff5640659052dfdfd69a; 22e8bd51bb0469d1a524130a057f894ff632376a up to, but not including, 34f2a2f32af570dfcc532ad70c080629ee1c32b0; 22e8bd51bb0469d1a524130a057f894ff632376a up to, but not including, b1a61366933224b3ad80975c4d01ac2cc6931ecf; 22e8bd51bb0469d1a524130a057f894ff632376a up to, but not including, a6c4250b81bd30beae94e1b7a4b26fa1193ad2e4; and 1 more rangescf1167292f606deaddac35ec384eba48f08a68d2, da926959bf791441ba06a80571708c3d0d3cc08f, 6f33d9d539fb94e5a17589c2dfe271ff9bb64904, 14995c4250f04b58bf6fc00e0e973a2e1b3cfb9b, 2419aa74081007dc4d14ff5640659052dfdfd69a, 34f2a2f32af570dfcc532ad70c080629ee1c32b0

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
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

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

Official description

In the Linux kernel, the following vulnerability has been resolved: rbd: Reset positive result codes to zero in object map update path In a reply message to an RBD request, a positive result code indicates a data payload, which is not allowed for writes. While rbd_osd_req_callback() already resets a positive result code for writes to zero, rbd_object_map_callback() does not. This allows a corrupted reply to an object map update to trigger the rbd_assert(*result < 0) in __rbd_obj_handle_request(). This happens, because rbd_object_map_callback() calls rbd_obj_handle_request() -> __rbd_obj_handle_request() and passes this positive result code. From __rbd_obj_handle_request(), rbd_obj_advance_write() is called, which leaves the positive result code unchanged and returns true. Therefore, the if(done && *result) branch is executed in __rbd_obj_handle_request() and the assertion triggers. This patch fixes the issue by adjusting the logic in the rbd_object_map_callback() path. A positive result code for an object map update is now reset to zero (similar to rbd_osd_req_callback()), and the message is subsequently handled the same way as if the result code was zero from the beginning. Additionally, a WARN_ON_ONCE() is added for this case.

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

The underlying weakness: Improper Input Validation

The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.

How developers prevent this class of flaw

  • Consider using language-theoretic security (LangSec) techniques that characterize inputs using a formal language and build recognizers for that language. This effectively requires parsing to be a distinct layer that effectively enforces a boundary between raw input and internal data representations, instead of allowing parser code to be scattered throughout the program, where it could be subject to errors or inconsistencies that create weaknesses.
  • Use an input validation framework such as Struts or the OWASP ESAPI Validation API. Note that using a framework does not automatically address all input validation problems; be mindful of weaknesses that could arise from misusing the framework itself (CWE-1173).
  • Understand all the potential areas where untrusted inputs can enter the product, including but not limited to: parameters or arguments, cookies, anything read from the network, environment variables, reverse DNS lookups, query results, request headers, URL components, e-mail, files, filenames, databases, and any external systems that provide data to the application. Remember that such inputs may be obtained indirectly through API calls.

More Improper Input Validation vulnerabilities (CWE-20)

Timeline

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

References

Recent Improper Input Validation vulnerabilities

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