Linux Distros Unpatched Vulnerability : CVE-2026-75805

medium Nessus Plugin ID 351160

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: A CMP client that requests certificate revocation on the basis of a PKCS#10 CSR may dereference a NULL pointer and terminate abnormally when processing a crafted revocation response. Impact summary: The NULL pointer dereference happens on a read which leads to a crash and a Denial of Service for the affected client application. CWE: CWE-476: NULL-pointer dereference Description: A CMP client revoking a certificate has to tell the server which certificate to revoke, and may do so by supplying a PKCS#10 CSR instead of the certificate itself or its issuer name and serial number. This is 'openssl cmp -cmd rr -csr <file>' on the command line, or OSSL_CMP_exec_RR_ses() with the certificate supplied via OSSL_CMP_CTX_set1_p10CSR() through the API. A CSR does not contain the issuer name and serial number of the certificate, so the client does not send them. A server may optionally name the certificate it revoked in its response, and the client then compares that name against what it sent. Having sent neither an issuer name nor a serial number, it has nothing to compare against, and a server returning a specially crafted name causes the client to read from a NULL pointer and crash. The revocation response is checked for valid message protection before the affected code is reached, so an attacker must be a malicious or compromised CMP server, or a man-in-the-middle in possession of the secret used for message protection.
Clients that identify the certificate to be revoked by a certificate or by issuer and serial number rather than by a PKCS#10 CSR are not affected. FIPS impact: no No FIPS modules are affected by this issue, as the CMP protocol implementation is outside the OpenSSL FIPS module boundary. (CVE-2026-75805)

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://access.redhat.com/security/cve/cve-2026-75805

https://security-tracker.debian.org/tracker/CVE-2026-75805

https://ubuntu.com/security/CVE-2026-75805

Plugin Details

Severity: Medium

ID: 351160

File Name: unpatched_CVE_2026_75805.nasl

Version: 1.2

Type: Local

Agent: unix

Family: Misc.

Published: 9/29/2026

Updated: 9/30/2026

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

Risk Information

VPR

Risk Factor: Low

Score: 1.2

Percentile: 0.01

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 4.3

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

CVSS Score Source: CVE-2026-75805

CVSS v3

Risk Factor: Medium

Base Score: 5.3

Temporal Score: 4.9

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

Temporal Vector: CVSS:3.0/E:U/RL:U/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, cpe:/o:centos:centos:7, cpe:/o:centos:centos:8, cpe:/o:debian:debian_linux:12.0, cpe:/o:debian:debian_linux:13.0, cpe:/o:debian:debian_linux:14.0, cpe:/o:redhat:enterprise_linux:10, cpe:/o:redhat:enterprise_linux:7, cpe:/o:redhat:enterprise_linux:8, cpe:/o:redhat:enterprise_linux:9, p-cpe:/a:canonical:ubuntu_linux:edk2-hwe, p-cpe:/a:canonical:ubuntu_linux:edk2, p-cpe:/a:canonical:ubuntu_linux:nodejs, p-cpe:/a:centos:centos:aavmf, p-cpe:/a:centos:centos:compat-openssl10, p-cpe:/a:centos:centos:compat-openssl11, p-cpe:/a:centos:centos:edk2-aarch64, p-cpe:/a:centos:centos:edk2-ovmf, p-cpe:/a:centos:centos:edk2-tools-doc, p-cpe:/a:centos:centos:edk2-tools, p-cpe:/a:centos:centos:edk2, p-cpe:/a:centos:centos:mingw-openssl, p-cpe:/a:centos:centos:mingw32-openssl, p-cpe:/a:centos:centos:mingw64-openssl, p-cpe:/a:centos:centos:mokutil, p-cpe:/a:centos:centos:openssl-devel, p-cpe:/a:centos:centos:openssl-libs, p-cpe:/a:centos:centos:openssl-perl, p-cpe:/a:centos:centos:openssl-static, p-cpe:/a:centos:centos:openssl, p-cpe:/a:centos:centos:ovmf, p-cpe:/a:centos:centos:shim-aa64, p-cpe:/a:centos:centos:shim-ia32, p-cpe:/a:centos:centos:shim-signed, p-cpe:/a:centos:centos:shim-unsigned-aarch64, p-cpe:/a:centos:centos:shim-unsigned-x64, p-cpe:/a:centos:centos:shim-x64, p-cpe:/a:centos:centos:shim, p-cpe:/a:debian:debian_linux:openssl, p-cpe:/a:redhat:enterprise_linux:aavmf, p-cpe:/a:redhat:enterprise_linux:compat-openssl10, p-cpe:/a:redhat:enterprise_linux:compat-openssl11, p-cpe:/a:redhat:enterprise_linux:edk2-aarch64, p-cpe:/a:redhat:enterprise_linux:edk2-ovmf, p-cpe:/a:redhat:enterprise_linux:edk2-tools-doc, p-cpe:/a:redhat:enterprise_linux:edk2-tools, p-cpe:/a:redhat:enterprise_linux:edk2, p-cpe:/a:redhat:enterprise_linux:mingw-openssl, p-cpe:/a:redhat:enterprise_linux:mingw32-openssl, p-cpe:/a:redhat:enterprise_linux:mingw64-openssl, p-cpe:/a:redhat:enterprise_linux:mokutil, p-cpe:/a:redhat:enterprise_linux:openssl-devel, p-cpe:/a:redhat:enterprise_linux:openssl-libs, p-cpe:/a:redhat:enterprise_linux:openssl-perl, p-cpe:/a:redhat:enterprise_linux:openssl-static, p-cpe:/a:redhat:enterprise_linux:openssl, p-cpe:/a:redhat:enterprise_linux:ovmf, p-cpe:/a:redhat:enterprise_linux:shim-aa64, p-cpe:/a:redhat:enterprise_linux:shim-ia32, p-cpe:/a:redhat:enterprise_linux:shim-signed, p-cpe:/a:redhat:enterprise_linux:shim-unsigned-aarch64, p-cpe:/a:redhat:enterprise_linux:shim-unsigned-x64, p-cpe:/a:redhat:enterprise_linux:shim-x64, p-cpe:/a:redhat:enterprise_linux:shim

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: 9/29/2026

Reference Information

CVE: CVE-2026-75805