CVE-2026-121996

Publication date 6 November 2026

Last updated 6 November 2026


Ubuntu priority

Cvss 3 Severity Score

8.2 · High

Score breakdown

Description

A length validation flaw in gdbserver's agent-expression parser allows an unauthenticated remote attacker to read uninitialized heap memory from the gdbserver process and cause a denial of service. Disclosed heap content includes addresses suitable for defeating ASLR in further exploitation.

Status

Package Ubuntu Release Status
gdb 26.10 stonking
Needs evaluation
26.04 LTS resolute
Needs evaluation
24.04 LTS noble
Needs evaluation
22.04 LTS jammy
Needs evaluation
20.04 LTS focal
Needs evaluation
18.04 LTS bionic
Needs evaluation
16.04 LTS xenial
Needs evaluation

Severity score breakdown

CVSS version: CVSS v3.0

Base score 8.2 · High

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H


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