CyberSecBulletin
CVE-2026-68432NVD status: Received

Linux: Incorrect Authorization

Published Updated By the CyberSecBulletin desk

CVE-2026-68432 is a high-severity incorrect authorization vulnerability in Linux, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions b95a8743e58f7efed5ddc4cb73829b66f17feab0, 7465ade989ba84adc2bfa58bad3ca25d249f0f7a, 0aa580a8bbbed2507b4582a1f0ef581d480d06ed 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 0.15% 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 b95a8743e58f7efed5ddc4cb73829b66f17feab0 or 7465ade989ba84adc2bfa58bad3ca25d249f0f7a or 0aa580a8bbbed2507b4582a1f0ef581d480d06ed or b3793d7dccb192ffff29894d11824db6251acdd5, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux8bcdc4f3a20be949df54b67e5ae2734daabb5792 up to, but not including, b95a8743e58f7efed5ddc4cb73829b66f17feab0; 8bcdc4f3a20be949df54b67e5ae2734daabb5792 up to, but not including, 7465ade989ba84adc2bfa58bad3ca25d249f0f7a; 8bcdc4f3a20be949df54b67e5ae2734daabb5792 up to, but not including, 0aa580a8bbbed2507b4582a1f0ef581d480d06ed; 8bcdc4f3a20be949df54b67e5ae2734daabb5792 up to, but not including, b3793d7dccb192ffff29894d11824db6251acdd5; 8bcdc4f3a20be949df54b67e5ae2734daabb5792 up to, but not including, 32d10c46bfde3e9b274e9e1bd6399d0ebea8f60f; 8bcdc4f3a20be949df54b67e5ae2734daabb5792 up to, but not including, 730c7e5fea7f06e0cdf21c547222ec93234fd1d6; 8bcdc4f3a20be949df54b67e5ae2734daabb5792 up to, but not including, e8ad0d311e225939a9a6c745d6cc384c7364ec87; 8bcdc4f3a20be949df54b67e5ae2734daabb5792 up to, but not including, 3a61bd9637f3d929aa846e4eb3d98b48c26fcb0e; and 1 more rangesb95a8743e58f7efed5ddc4cb73829b66f17feab0, 7465ade989ba84adc2bfa58bad3ca25d249f0f7a, 0aa580a8bbbed2507b4582a1f0ef581d480d06ed, b3793d7dccb192ffff29894d11824db6251acdd5, 32d10c46bfde3e9b274e9e1bd6399d0ebea8f60f, 730c7e5fea7f06e0cdf21c547222ec93234fd1d6

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
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
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:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H. Scored by CNA.

Official description

In the Linux kernel, the following vulnerability has been resolved: vxlan: require CAP_NET_ADMIN in the device netns for changelink A tunnel changelink() operates on at most two netns, dev_net(dev) and the sticky underlay netns vxlan->net. They differ once the device is created in or moved to a netns other than the one the request runs in. The rtnl changelink path checks CAP_NET_ADMIN only against dev_net(dev), so a caller privileged there but not in vxlan->net can rewrite a vxlan device whose underlay lives in vxlan->net. vxlan_changelink() validates and applies the new configuration against vxlan->net (vxlan_config_validate(vxlan->net, ...)) and can reopen the underlay socket in that netns, so the same reasoning as the tunnel changelink series applies here. Gate vxlan_changelink() with rtnl_dev_link_net_capable(), at the top of the op before any attribute is parsed, matching ipgre_changelink() and the rest of the "require CAP_NET_ADMIN in the device netns for changelink" series. Found by 0sec automated security-research tooling (https://0sec.ai).

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

The underlying weakness: Incorrect Authorization

The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.

How developers prevent this class of flaw

  • Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) to enforce the roles at the appropriate boundaries. Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
  • Ensure that access control checks are performed related to the business logic. These checks may be different than the access control checks that are applied to more generic resources such as files, connections, processes, memory, and database records. For example, a database may restrict access for medical records to a specific database user, but each record might only be intended to be accessible to the patient and the patient's doctor.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using authorization frameworks such as the JAAS Authorization Framework and the OWASP ESAPI Access Control feature.

More Incorrect Authorization vulnerabilities (CWE-863)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Incorrect Authorization vulnerabilities

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