---
id: CVE-2026-121995
title: >-
  Gdb: gdb: stack buffer overflow in parse_tracepoint_definition via stale
  rs->buf tail
summary: >-
  A stack buffer overflow in the GDB client's tracepoint upload handler allows
  an attacker-controlled debug stub to corrupt stack memory automatically during
  connection setup. The overflow results from GDB reading beyond the current
  reply …
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H'
cvssSource: cna
cwe:
  - CWE-121
vendor: Red Hat
product: crash
affected:
  - crash
  - gdb (all versions)
  - gdb (all versions)
  - gdb (all versions)
  - crash
  - gcc-toolset-14-gdb (all versions)
  - gcc-toolset-15-gdb (all versions)
  - gdb (all versions)
  - crash
  - gdb (all versions)
  - gdb (all versions)
published: '2026-11-05'
updated: '2026-11-05'
sourceUpdated: '2026-11-05T16:08:49.660Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-121995'
references:
  - url: 'https://access.redhat.com/security/cve/CVE-2026-121995'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2565677'
    label: RHBZ#2565677
tags:
  - cve.org
ingestedAt: '2026-11-05T22:38:31.330Z'
---

## Overview

A stack buffer overflow in the GDB client's tracepoint upload handler allows an attacker-controlled debug stub to corrupt stack memory automatically during connection setup. The overflow results from GDB reading beyond the current reply boundary into a stale prior reply in the shared packet buffer.

## Affected

- `crash`
- `gdb (all versions)`
- `gdb (all versions)`
- `gdb (all versions)`
- `crash`
- `gcc-toolset-14-gdb (all versions)`
- `gcc-toolset-15-gdb (all versions)`
- `gdb (all versions)`
- `crash`
- `gdb (all versions)`
- `gdb (all versions)`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

### Workarounds

There is no mitigation for this vulnerability. Users should only connect GDB to trusted debug targets.