Bug 2451615 (CVE-2026-4878) - CVE-2026-4878 libcap: libcap: Privilege escalation via TOCTOU race condition in cap_set_file()
Summary: CVE-2026-4878 libcap: libcap: Privilege escalation via TOCTOU race condition ...
Keywords:
Status: NEW
Alias: CVE-2026-4878
Deadline: 2026-04-06
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
high
high
Target Milestone: ---
Assignee: Product Security
QA Contact:
URL:
Whiteboard:
Depends On: 2447554 2481143
Blocks:
TreeView+ depends on / blocked
 
Reported: 2026-03-26 06:56 UTC by OSIDB Bzimport
Modified: 2026-06-17 17:17 UTC (History)
4 users (show)

Fixed In Version:
Clone Of:
Environment:
Last Closed:
Embargoed:


Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHBA-2026:13279 0 None None None 2026-05-04 01:03:01 UTC
Red Hat Product Errata RHBA-2026:13347 0 None None None 2026-05-04 06:21:46 UTC
Red Hat Product Errata RHBA-2026:13348 0 None None None 2026-05-04 06:21:53 UTC
Red Hat Product Errata RHBA-2026:13349 0 None None None 2026-05-04 06:30:49 UTC
Red Hat Product Errata RHBA-2026:13410 0 None None None 2026-05-04 11:14:38 UTC
Red Hat Product Errata RHBA-2026:13433 0 None None None 2026-05-04 12:17:41 UTC
Red Hat Product Errata RHBA-2026:13435 0 None None None 2026-05-04 12:20:31 UTC
Red Hat Product Errata RHBA-2026:13502 0 None None None 2026-05-04 13:42:17 UTC
Red Hat Product Errata RHBA-2026:13506 0 None None None 2026-05-04 13:51:29 UTC
Red Hat Product Errata RHBA-2026:13528 0 None None None 2026-05-04 16:23:58 UTC
Red Hat Product Errata RHBA-2026:13572 0 None None None 2026-05-05 00:04:24 UTC
Red Hat Product Errata RHBA-2026:13622 0 None None None 2026-05-05 07:40:31 UTC
Red Hat Product Errata RHBA-2026:13633 0 None None None 2026-05-05 10:26:00 UTC
Red Hat Product Errata RHBA-2026:13760 0 None None None 2026-05-05 17:24:29 UTC
Red Hat Product Errata RHBA-2026:13929 0 None None None 2026-05-06 10:18:33 UTC
Red Hat Product Errata RHBA-2026:13930 0 None None None 2026-05-06 11:28:05 UTC
Red Hat Product Errata RHBA-2026:14225 0 None None None 2026-05-06 16:45:24 UTC
Red Hat Product Errata RHBA-2026:16109 0 None None None 2026-05-12 01:09:13 UTC
Red Hat Product Errata RHBA-2026:16110 0 None None None 2026-05-12 01:37:50 UTC
Red Hat Product Errata RHBA-2026:19538 0 None None None 2026-05-20 06:31:41 UTC
Red Hat Product Errata RHSA-2026:12423 0 None None None 2026-04-30 17:40:36 UTC
Red Hat Product Errata RHSA-2026:12441 0 None None None 2026-04-30 18:47:27 UTC
Red Hat Product Errata RHSA-2026:13285 0 None None None 2026-05-04 01:38:11 UTC
Red Hat Product Errata RHSA-2026:19130 0 None None None 2026-05-19 16:05:03 UTC
Red Hat Product Errata RHSA-2026:19346 0 None None None 2026-05-19 21:37:17 UTC
Red Hat Product Errata RHSA-2026:19456 0 None None None 2026-05-20 02:16:42 UTC
Red Hat Product Errata RHSA-2026:19458 0 None None None 2026-05-20 03:49:26 UTC
Red Hat Product Errata RHSA-2026:20595 0 None None None 2026-05-26 05:04:44 UTC
Red Hat Product Errata RHSA-2026:21254 0 None None None 2026-05-27 07:06:31 UTC
Red Hat Product Errata RHSA-2026:22957 0 None None None 2026-06-03 20:18:26 UTC
Red Hat Product Errata RHSA-2026:23233 0 None None None 2026-06-11 07:53:31 UTC
Red Hat Product Errata RHSA-2026:23245 0 None None None 2026-06-10 09:16:23 UTC
Red Hat Product Errata RHSA-2026:24346 0 None None None 2026-06-08 02:05:21 UTC
Red Hat Product Errata RHSA-2026:25181 0 None None None 2026-06-17 17:17:33 UTC

Description OSIDB Bzimport 2026-03-26 06:56:43 UTC
A time-of-check-to-time-of-use (TOCTOU) race condition in libcap’s cap_set_file() allows a local unprivileged user to redirect file capability updates to an attacker‑controlled file and gain elevated privileges. The function first validates the target path with lstat() (which does not follow symlinks) and enforces that it is a regular, non‑symlink file, but then applies or removes security.capability using setxattr() / removexattr(), which re-resolve the path and do follow symlinks. An attacker with write access to the parent directory can exploit the window between these calls by atomically swapping the validated regular file with a symlink or alternate file using renameat2(RENAME_EXCHANGE). As a result, capabilities can be injected into or stripped from an unintended executable, for example when a privileged process (such as setcap, package scripts, or container tooling) invokes cap_set_file() on an attacker-influenced path. This can be abused to grant capabilities like CAP_SETUID to an attacker’s binary and escalate to root.

Comment 3 errata-xmlrpc 2026-04-30 17:40:30 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:12423 https://access.redhat.com/errata/RHSA-2026:12423

Comment 4 errata-xmlrpc 2026-04-30 18:47:26 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:12441 https://access.redhat.com/errata/RHSA-2026:12441

Comment 5 errata-xmlrpc 2026-05-04 01:38:10 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2026:13285 https://access.redhat.com/errata/RHSA-2026:13285

Comment 9 errata-xmlrpc 2026-05-19 16:05:02 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10

Via RHSA-2026:19130 https://access.redhat.com/errata/RHSA-2026:19130

Comment 10 errata-xmlrpc 2026-05-19 21:37:16 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9

Via RHSA-2026:19346 https://access.redhat.com/errata/RHSA-2026:19346

Comment 11 errata-xmlrpc 2026-05-20 02:16:41 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 10.0 Extended Update Support

Via RHSA-2026:19456 https://access.redhat.com/errata/RHSA-2026:19456

Comment 12 errata-xmlrpc 2026-05-20 03:49:25 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.6 Extended Update Support

Via RHSA-2026:19458 https://access.redhat.com/errata/RHSA-2026:19458

Comment 16 errata-xmlrpc 2026-05-26 05:04:43 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.4 Extended Update Support

Via RHSA-2026:20595 https://access.redhat.com/errata/RHSA-2026:20595

Comment 18 errata-xmlrpc 2026-05-27 07:06:30 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

Via RHSA-2026:21254 https://access.redhat.com/errata/RHSA-2026:21254

Comment 21 errata-xmlrpc 2026-06-03 20:18:25 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions
  Red Hat Enterprise Linux 8.8 Telecommunications Update Service

Via RHSA-2026:22957 https://access.redhat.com/errata/RHSA-2026:22957

Comment 22 restoresturdy 2026-06-05 03:06:21 UTC
The following items have addressed this issue. Support for Red Hat Enterprise Linux 10.0 Extended Updates https://access.redhat.com/errata/RHSA-2026:22957 https://5letter-words.io

Comment 23 errata-xmlrpc 2026-06-08 02:05:20 UTC
This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support
  Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On

Via RHSA-2026:24346 https://access.redhat.com/errata/RHSA-2026:24346

Comment 24 errata-xmlrpc 2026-06-10 09:16:22 UTC
This issue has been addressed in the following products:

  Red Hat OpenShift Container Platform 4.19

Via RHSA-2026:23245 https://access.redhat.com/errata/RHSA-2026:23245

Comment 26 errata-xmlrpc 2026-06-11 07:53:30 UTC
This issue has been addressed in the following products:

  Red Hat OpenShift Container Platform 4.15

Via RHSA-2026:23233 https://access.redhat.com/errata/RHSA-2026:23233

Comment 27 errata-xmlrpc 2026-06-17 17:17:32 UTC
This issue has been addressed in the following products:

  Red Hat OpenShift Container Platform 4.18

Via RHSA-2026:25181 https://access.redhat.com/errata/RHSA-2026:25181


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