9.8Critical

CVE-2020-37239

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.

What this means for your business

  • An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.

What to do

  1. 1Ask your IT team or provider whether any of your systems use the affected product.
  2. 2If you do, follow the vendor's guidance. No patch reference has been published yet.

Fastnexa security experts

Not sure if your company is exposed to CVE-2020-37239?

Tell us where you run the affected software and a Fastnexa penetration tester will check whether this flaw, or others like it, can be used against your websites, apps and network.

The full test is free for our first 10 founding clients until 31 December 2026. See the offer

Book a 30-min callWhatsApp us

Think you’ve already been hit? Don’t wait on a form: call or WhatsApp +1 (732) 454 2616. We reply within 1 hour, 24/7. Emergency help →

Scoring

CVSS
9.8 (v3.1)
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v4
9.3
Weakness
CWE-415
Assigned by
disclosure@vulncheck.com

Dates

Published
2026-05-16
Last modified
2026-09-29
Sources
NVD

References

CVE-2020-37239 | CyberBrief