CyberSecBulletin
CVE-2026-68142NVD status: Received

Linux: Missing Authorization

Published Updated By the CyberSecBulletin desk

CVE-2026-68142 is a high-severity missing 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 a5522963c57f12df5f9db804ebfc472b58eef0ae, 278c6a31ee27c931c722202c8c06cc3253923254, 11a7d989d00160481a273eb4f7f05f64b5a6ffdf 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 0.12% 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 a5522963c57f12df5f9db804ebfc472b58eef0ae or 278c6a31ee27c931c722202c8c06cc3253923254 or 11a7d989d00160481a273eb4f7f05f64b5a6ffdf or 2abdacc927c92fa6a9cc8341e8c9b88dcb561553, whichever matches your release line, or a later version.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux5b861f6baa3a22a48d7a4ad0ce38a223d36c978a up to, but not including, a5522963c57f12df5f9db804ebfc472b58eef0ae; 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a up to, but not including, 278c6a31ee27c931c722202c8c06cc3253923254; 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a up to, but not including, 11a7d989d00160481a273eb4f7f05f64b5a6ffdf; 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a up to, but not including, 2abdacc927c92fa6a9cc8341e8c9b88dcb561553; 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a up to, but not including, 9de5518fc1fab583526a8f66b8e505c4864dc60a; 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a up to, but not including, f8c498585d2a08aa623748353c3e61467b7e9fd2; 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a up to, but not including, 95f45e20f1b2cec13823f0f68060ab4b2261b2c1; 5b861f6baa3a22a48d7a4ad0ce38a223d36c978a up to, but not including, 8efb8f8bbb353b8f2fdf4f37534c6d96c9f69e01; and 1 more rangesa5522963c57f12df5f9db804ebfc472b58eef0ae, 278c6a31ee27c931c722202c8c06cc3253923254, 11a7d989d00160481a273eb4f7f05f64b5a6ffdf, 2abdacc927c92fa6a9cc8341e8c9b88dcb561553, 9de5518fc1fab583526a8f66b8e505c4864dc60a, f8c498585d2a08aa623748353c3e61467b7e9fd2

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: geneve: 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 geneve->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 geneve->net can rewrite a geneve device whose underlay lives in geneve->net. geneve_changelink() applies the new configuration against geneve->net: geneve_link_config() and the geneve_quiesce()/geneve_unquiesce() pair reopen the underlay sockets in that netns (geneve_sock_add() uses geneve->net), so the same reasoning as the tunnel changelink series applies here. Gate geneve_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: Missing Authorization

The product does not perform an authorization check when an actor attempts to access a resource or perform an action.

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 Missing Authorization vulnerabilities (CWE-862)

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 Missing Authorization vulnerabilities

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