Linux Distros Unpatched Vulnerability : CVE-2026-88823

critical Nessus Plugin ID 378238

Synopsis

The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.

Description

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

- Issue summary: The AES-GCM-SIV implementation treats a zero-length Additional Authenticated Data (AAD) update as a reset of all the AAD supplied so far, instead of leaving the AAD unchanged. An application that supplies its AAD in several fragments, one of which is empty, therefore produces or verifies messages whose authentication tag does not cover the AAD supplied before the empty fragment. Impact summary: Data an application intended to authenticate alongside a message is silently left unauthenticated. An attacker can forge the AAD of such a message. CWE: CWE-325: Missing Cryptographic Step Description: An application passing AAD in multiple chunks of which some have zero length will have the previous AAD chunks effectively unauthenticated. Also, on context re-initialisation, the AAD was not reset, which meant that any AAD accumulated from the previous context usage were also included in the AAD of the new message.
The fix makes a zero-length AAD update a no-op and clears any accumulated AAD whenever the context is re- initialised with a key or a nonce. A re-initialisation that only changes parameters keeps the AAD. FIPS impact: no The FIPS modules are not affected, as AES-GCM-SIV is not a FIPS approved algorithm and is implemented only in the default provider, outside the OpenSSL FIPS module boundary. Fixed in OpenSSL 3.5.10 (Affected since 3.5.0). (CVE-2026-88823)

Note that Nessus relies on the presence of the package as reported by the vendor.

Solution

There is no known solution at this time.

See Also

https://security-tracker.debian.org/tracker/CVE-2026-88823

Plugin Details

Severity: Critical

ID: 378238

File Name: unpatched_CVE_2026_88823.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Misc.

Published: 11/10/2026

Updated: 11/10/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3

Percentile: 23.88

CVSS v2

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.4

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

CVSS Score Source: CVE-2026-88823

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 9

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

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

Vulnerability Information

CPE: cpe:/o:debian:debian_linux:12.0, cpe:/o:debian:debian_linux:13.0, cpe:/o:debian:debian_linux:14.0, p-cpe:/a:debian:debian_linux:openssl

Required KB Items: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched, Host/OS/identifier

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 11/10/2026

Reference Information

CVE: CVE-2026-88823