Ubuntu 22.04 LTS / 24.04 LTS / 26.04 LTS / 26.10 : nginx vulnerabilities (USN-8955-1)

critical Nessus Plugin ID 372414

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 / 26.10 host has packages installed that are affected by multiple vulnerabilities as referenced in the USN-8955-1 advisory.

It was discovered that nginx incorrectly handled certain configurations using the alias directive together with rewrite rules. A remote attacker could possibly use this issue to cause nginx to crash, resulting in a denial of service, or execute arbitrary code. (CVE-2026-15176)

It was discovered that nginx incorrectly handled map directives using regex matching under certain circumstances. A remote attacker could possibly use this issue to cause nginx to crash, resulting in a denial of service, or execute arbitrary code. (CVE-2026-93479)

It was discovered that nginx incorrectly handled HTTP/3 requests when proxy_request_buffering was enabled.
This issue only affected Ubuntu 26.04 LTS and Ubuntu 26.10. A remote attacker could possibly use this issue to inject data into proxied requests. (CVE-2026-95101)

It was discovered that nginx incorrectly handled asynchronous file I/O in certain configurations with Server Side Includes pages. A remote attacker could possibly use this issue to cause nginx to crash, resulting in a denial of service, or execute arbitrary code. (CVE-2026-97205)

It was discovered that nginx incorrectly handled SSL session ticket keys when configured with a shared session cache but without explicit ticket key rotation. This issue only affected Ubuntu 24.04 LTS, Ubuntu 26.04 LTS, and Ubuntu 26.10. A remote attacker could possibly use this issue to forge client SSL sessions and bypass client certificate verification. (CVE-2026-97629)

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-8955-1

Plugin Details

Severity: Critical

ID: 372414

File Name: ubuntu_USN-8955-1.nasl

Version: 1.1

Type: Local

Agent: unix

Published: 10/27/2026

Updated: 10/27/2026

Supported Sensors: Nessus Agent, Continuous Assessment, Nessus

Risk Information

VPR

Risk Factor: High

Score: 7.9

Percentile: 99.33

CVSS v2

Risk Factor: High

Base Score: 7.6

Temporal Score: 6

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

CVSS Score Source: CVE-2026-97205

CVSS v3

Risk Factor: High

Base Score: 8.1

Temporal Score: 7.3

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

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

CVSS v4

Risk Factor: Critical

Base Score: 9.2

Threat Score: 8.2

Threat Vector: CVSS:4.0/E:P

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

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, cpe:/o:canonical:ubuntu_linux:26.10, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-auth-pam, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-cache-purge, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-dav-ext, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-echo, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-fancyindex, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-geoip2, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-geoip, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-headers-more-filter, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-image-filter, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-ndk, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-perl, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-subs-filter, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-uploadprogress, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-upstream-fair, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-http-xslt-filter, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-mail, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-nchan, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-rtmp, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-stream-geoip2, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-stream-geoip, p-cpe:/a:canonical:ubuntu_linux:libnginx-mod-stream, p-cpe:/a:canonical:ubuntu_linux:nginx-common, p-cpe:/a:canonical:ubuntu_linux:nginx-core, p-cpe:/a:canonical:ubuntu_linux:nginx-extras, p-cpe:/a:canonical:ubuntu_linux:nginx-full, p-cpe:/a:canonical:ubuntu_linux:nginx-light, p-cpe:/a:canonical:ubuntu_linux:nginx

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

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 10/26/2026

Vulnerability Publication Date: 10/14/2026

Reference Information

CVE: CVE-2026-15176, CVE-2026-93479, CVE-2026-95101, CVE-2026-97205, CVE-2026-97629

IAVA: 2026-A-1142

USN: 8955-1