Detections
Analytics

Ubuntu 22.04 LTS / 24.04 LTS / 26.04 LTS : Exim vulnerabilities (USN-8834-1)

high Nessus Plugin ID 350975

Synopsis

The remote Ubuntu host is missing one or more security updates.

Description

The remote Ubuntu 22.04 LTS / 24.04 LTS / 26.04 LTS host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-8834-1 advisory.

 It was discovered that Exim had an out-of-bounds write when Proxy-Protocol was used with an attacker- controlled proxy. A remote attacker could possibly use this issue to execute arbitrary code.
 (CVE-2026-94054)

 It was discovered that Exim had a use-after-free when certain non-default TLS settings were used with GnuTLS. A remote attacker could possibly use this issue to cause Exim to crash, resulting in a denial of service. This issue only affected Ubuntu 26.04 LTS. (CVE-2026-94055)

 It was discovered that Exim allowed attackers to read uninitialized data from stack memory when Proxy- Protocol was used with an attacker-controlled proxy. A remote attacker could possibly use this issue to obtain sensitive information. (CVE-2026-94056)

 It was discovered that Exim allowed SMTP smuggling via crafted data sent after a rejection during DATA processing. A remote attacker could possibly use this issue to inject arbitrary email messages.
 (CVE-2026-94057)

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

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

Solution

Update the affected packages.

See Also

https://ubuntu.com/security/notices/USN-8834-1

Plugin Details

Severity: High

ID: 350975

File Name: ubuntu_USN-8834-1.nasl

Version: 1.2

Type: Local

Agent: unix

Published: 9/29/2026

Updated: 9/29/2026

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Azure, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Continuous Assessment, Tenable Cloud Security, Tenable Self-Hosted Container Security, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3.2

Percentile: 50.43

CVSS v2

Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

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

CVSS Score Source: CVE-2026-94056

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

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

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

Vulnerability Information

CPE: cpe:/o:canonical:ubuntu_linux:22.04:-:lts, cpe:/o:canonical:ubuntu_linux:24.04:-:lts, cpe:/o:canonical:ubuntu_linux:26.04:-:lts, p-cpe:/a:canonical:ubuntu_linux:exim4-base, p-cpe:/a:canonical:ubuntu_linux:exim4-config, p-cpe:/a:canonical:ubuntu_linux:exim4-daemon-heavy, p-cpe:/a:canonical:ubuntu_linux:exim4-daemon-light, p-cpe:/a:canonical:ubuntu_linux:exim4, p-cpe:/a:canonical:ubuntu_linux:eximon4

Required KB Items: Host/cpu, Host/Debian/dpkg-l, Host/Ubuntu, Host/Ubuntu/release

Exploit Ease: No known exploits are available

Patch Publication Date: 9/28/2026

Vulnerability Publication Date: 9/19/2026

Reference Information

CVE: CVE-2026-94054, CVE-2026-94055, CVE-2026-94056, CVE-2026-94057

USN: 8834-1