Echo: libevent: security update to 2.1.12-stable-10+e1

medium Tenable Self-Hosted Container Security Plugin ID 455575

Description

There are packages installed that are affected by a vulnerability referenced in the following CVE:

- Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has a use-after-free
in buffer.c when evbuffer_add_buffer_reference processes an output buffer whose out_total_len is zero.
evbuffer_free_all_chains frees the initial empty chain without resetting outbuf->first, outbuf->last, or
outbuf->last_with_datap, and APPEND_CHAIN_MULTICAST subsequently dereferences the dangling chain pointer.
A caller that can drive this buffer state can cause memory corruption or a process crash. This issue is
fixed in versions 2.1.13 and 2.2.2-alpha. (CVE-2026-63381)

Solution

Update the libevent library and its related packages to version 2.1.12-stable-10+e1 or later.

See Also

https://advisory.echohq.com/cve/CVE-2026-63381

Plugin Details

Severity: Medium

ID: 455575

Version: Revision 1.2

Type: Local

Published: 10/1/2026

Updated: 10/2/2026

Supported Sensors: Tenable Cloud Security, Tenable Self-Hosted Container Security

Risk Information

VPR

Risk Factor: Low

Score: 3.9

Percentile: 52.44

CVSS v2

Risk Factor: Medium

Base Score: 5.7

Temporal Score: 4.2

Vector: CVSS2#AV:L/AC:L/Au:S/C:P/I:P/A:C

CVSS Score Source: CVE-2026-63381

CVSS v3

Risk Factor: Medium

Base Score: 6.6

Temporal Score: 5.8

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

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

CVSS v4

Risk Factor: Medium

Base Score: 5.8

Threat Score: 2

Threat Vector: CVSS:4.0/E:U

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

Vulnerability Information

Exploit Ease: No known exploits are available

Patch Publication Date: 8/21/2026

Vulnerability Publication Date: 8/20/2026

Reference Information

CVE: CVE-2026-63381