Unity Linux 20.1050a / 20.1060a / 20.1070a Security Update: libevent (UTSA-2026-124537)

critical Nessus Plugin ID 349889

Synopsis

The Unity Linux host is missing one or more security updates.

Description

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2026-124537 advisory.

Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, the libevent evhttp parser in http.c inconsistently handles duplicate Transfer-Encoding headers, comma-separated Transfer-Encoding values, and bare line feeds in chunked framing. evhttp_find_header can select only the first header, evhttp_check_transfer_encoding_ was absent so the previous whole-string comparison fails to recognize valid lists ending in chunked, and evhttp_handle_chunked_read uses EVBUFFER_EOL_CRLF rather than EVBUFFER_EOL_CRLF_STRICT, accepting bare LF chunk terminators. When libevent is deployed behind a proxy that frames the same request differently, an unauthenticated remote attacker can desynchronize request boundaries and smuggle a second request, potentially bypassing access controls or poisoning caches. This issue is fixed in versions 2.1.13 and 2.2.2-alpha.

Tenable has extracted the preceding description block directly from the Unity Linux security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Update the affected libevent package.

See Also

https://access.redhat.com/security/cve/CVE-2026-63382

https://github.com/libevent/libevent/releases/tag/release-2.2.2-alpha

http://www.nessus.org/u?16f87941

http://www.nessus.org/u?62981726

http://www.nessus.org/u?6ea8c818

http://www.nessus.org/u?71a665ce

http://www.nessus.org/u?8432cbe8

http://www.nessus.org/u?c125ce75

http://www.nessus.org/u?e8814845

Plugin Details

Severity: Critical

ID: 349889

File Name: unity_linux_UTSA-2026-124537.nasl

Version: 1.1

Type: Local

Published: 9/24/2026

Updated: 9/24/2026

Supported Sensors: Nessus

Risk Information

VPR

Risk Factor: Medium

Score: 4.5

Percentile: 57.59

CVSS v2

Risk Factor: High

Base Score: 7.3

Temporal Score: 5.4

Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:C/A:P

CVSS Score Source: CVE-2026-63382

CVSS v3

Risk Factor: High

Base Score: 7.7

Temporal Score: 6.7

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

CVSS v4

Risk Factor: Critical

Base Score: 9.2

Threat Score: 7.1

Threat Vector: CVSS:4.0/E:U

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:L/SC:L/SI:L/SA:N

Vulnerability Information

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/UOS-Server/release, Host/UOS-Server/rpm-list

Exploit Ease: No known exploits are available

Patch Publication Date: 9/25/2026

Vulnerability Publication Date: 8/20/2026

Reference Information

CVE: CVE-2026-63382