CVE-2026-4878
Libcap: libcap: privilege escalation via toctou race condition in cap_set_file()
Description
A flaw was found in libcap. A local unprivileged user can exploit a Time-of-check-to-time-of-use (TOCTOU) race condition in the `cap_set_file()` function. This allows an attacker with write access to a parent directory to redirect file capability updates to an attacker-controlled file. By doing so, capabilities can be injected into or stripped from unintended executables, leading to privilege escalation.
INFO
Published Date :
April 9, 2026, 4:16 p.m.
Last Modified :
April 9, 2026, 4:16 p.m.
Remotely Exploit :
No
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-4878
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | 53f830b8-0a3f-465b-8143-3b8a9948e749 | ||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 3.1 | MEDIUM | MITRE-CVE |
Solution
- Update the libcap library to the latest version.
- Review file system access controls for sensitive directories.
- Monitor for unexpected changes in file capabilities.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-4878.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-4878 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-4878
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-4878 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-4878 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Apr. 09, 2026
Action Type Old Value New Value Added Description A flaw was found in libcap. A local unprivileged user can exploit a Time-of-check-to-time-of-use (TOCTOU) race condition in the `cap_set_file()` function. This allows an attacker with write access to a parent directory to redirect file capability updates to an attacker-controlled file. By doing so, capabilities can be injected into or stripped from unintended executables, leading to privilege escalation. Added CVSS V3.1 AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H Added CWE CWE-367 Added Reference https://access.redhat.com/security/cve/CVE-2026-4878 Added Reference https://bugzilla.redhat.com/show_bug.cgi?id=2447554 Added Reference https://bugzilla.redhat.com/show_bug.cgi?id=2451615 -
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Apr. 09, 2026
Action Type Old Value New Value Added Reference http://www.openwall.com/lists/oss-security/2026/04/07/14 Added Reference http://www.openwall.com/lists/oss-security/2026/04/07/4 Added Reference http://www.openwall.com/lists/oss-security/2026/04/08/9 Added Reference http://www.openwall.com/lists/oss-security/2026/04/09/5 Added Reference http://www.openwall.com/lists/oss-security/2026/04/09/6