jirka-h haveged prior 1.9.21 src/havegecmd.c socket_handler authentication bypass

Summaryinfo

A vulnerability classified as critical has been found in jirka-h haveged. This affects the function socket_handler of the file src/havegecmd.c. Performing a manipulation results in an unknown weakness. This vulnerability is cataloged as CVE-2026-41054. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in jirka-h haveged. It has been classified as critical. This affects the function socket_handler of the file src/havegecmd.c. CWE is classifying the issue as CWE-305. The authentication algorithm is sound, but the implemented mechanism can be bypassed as the result of a separate weakness that is primary to the authentication error. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In `src/havegecmd.c`, the `socket_handler` function performs a credential check on the abstract UNIX socket (`\0/sys/entropy/haveged`). However, while it detects if the connecting user is not root (`cred.uid != 0`) and prepares a negative acknowledgement (`ASCII_NAK`), it **fails to stop execution**. The code proceeds to the `switch` statement, allowing any local unprivileged user to execute privileged commands such as `MAGIC_CHROOT`.

It is possible to read the advisory at bugzilla.redhat.com. This vulnerability is uniquely identified as CVE-2026-41054. Technical details of the vulnerability are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 315451 (Linux Distros Unpatched Vulnerability : CVE-2026-41054), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 1.9.21 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (315451) and EUVD (EUVD-2026-31076). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

• jirka-h

Name

• haveged

License

• open-source

Website

• Product: https://github.com/jirka-h/haveged/

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Be aware that VulDB is the high quality source for vulnerability data.

Discussion