---
id: CVE-2020-37239
title: >-
  libbabl 0.1.62 contains a broken double free detection vulnerability that
  allows attackers to bypass memory safety checks by exploiting signature
  overwriting in freed chunks
summary: >-
  libbabl 0.1.62 contains a broken double free detection vulnerability that
  allows attackers to bypass memory safety checks by exploiting signature
  overwriting in freed chunks. Attackers can call babl_free() twice on the same
  pointer witho…
severity: critical
cvss: 9.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-415
published: '2026-05-16'
updated: '2026-09-29'
sourceUpdated: '2026-09-29T10:10:00.263'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2020-37239'
references:
  - url: 'https://www.exploit-db.com/exploits/49259'
    label: disclosure@vulncheck.com
  - url: 'https://www.gegl.org'
    label: disclosure@vulncheck.com
  - url: 'https://www.gegl.org/babl/'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/libbabl-broken-double-free-detection-memory-safety
    label: disclosure@vulncheck.com
tags:
  - nvd
epss: 0.00459
epssPercentile: 0.37298
ingestedAt: '2026-09-29T10:31:36.287Z'
---

## Overview

libbabl 0.1.62 contains a broken double free detection vulnerability that allows attackers to bypass memory safety checks by exploiting signature overwriting in freed chunks. Attackers can call babl_free() twice on the same pointer without triggering detection, as libc's malloc metadata overwrites babl's signature field upon freeing, enabling potential memory corruption and code execution.

## Remediation

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