libcap up to 2.77 cap_set_file allocation of resources

Summaryinfo

A vulnerability labeled as critical has been found in libcap up to 2.77. Affected by this issue is the function cap_set_file. The manipulation results in allocation of resources. This vulnerability is identified as CVE-2026-4878. The attack is only possible with local access. There is not any exploit available. Applying a patch is advised to resolve this issue.

Detailsinfo

A vulnerability, which was classified as critical, was found in libcap up to 2.77. Affected is the function cap_set_file. The manipulation with an unknown input leads to a allocation of resources vulnerability. CWE is classifying the issue as CWE-770. The product allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

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.

The advisory is shared for download at seclists.org. This vulnerability is traded as CVE-2026-4878. The exploitability is told to be difficult. The attack needs to be approached locally. There are known technical details, but no exploit is available.

The vulnerability scanner Nessus provides a plugin with the ID 305106 (Linux Distros Unpatched Vulnerability : CVE-2026-4878), which helps to determine the existence of the flaw in a target environment.

Applying the patch 286ace1259992bd0c5d9016715833f2e148ac596 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org.

The vulnerability is also documented in the databases at Tenable (305106), EUVD (EUVD-2026-20910) and CERT Bund (WID-SEC-2026-1267). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Affected

• Red Hat Enterprise Linux
• Fedora Linux
• SUSE Linux
• Oracle Linux
• RESF Rocky Linux
• IBM MQ
• Debian Linux

Productinfo

Name

• libcap

Version

• 2.0
• 2.1
• 2.2
• 2.3
• 2.4
• 2.5
• 2.6
• 2.7
• 2.8
• 2.9
• 2.10
• 2.11
• 2.12
• 2.13
• 2.14
• 2.15
• 2.16
• 2.17
• 2.18
• 2.19
• 2.20
• 2.21
• 2.22
• 2.23
• 2.24
• 2.25
• 2.26
• 2.27
• 2.28
• 2.29
• 2.30
• 2.31
• 2.32
• 2.33
• 2.34
• 2.35
• 2.36
• 2.37
• 2.38
• 2.39
• 2.40
• 2.41
• 2.42
• 2.43
• 2.44
• 2.45
• 2.46
• 2.47
• 2.48
• 2.49
• 2.50
• 2.51
• 2.52
• 2.53
• 2.54
• 2.55
• 2.56
• 2.57
• 2.58
• 2.59
• 2.60
• 2.61
• 2.62
• 2.63
• 2.64
• 2.65
• 2.66
• 2.67
• 2.68
• 2.69
• 2.70
• 2.71
• 2.72
• 2.73
• 2.74
• 2.75
• 2.76
• 2.77

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Discussion