CVE-2026-111125 CFITSIO through 4.7.0 Heap Out-of-Bounds Read via HCOMPRESS input_nnybble

Medium 6.9 Published 15 Oct 2026 Updated 21 Oct 2026

Attackers can cause crashes or leak heap memory by providing crafted FITS files to applications using the CFITSIO library.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Local or same network only
Victim action needed: A user has to click or open something
Fix: Available

What is CVE-2026-111125?

CVE-2026-111125 is a medium-severity memory corruption vulnerability in HEASARC cfitsio, published on 15 Oct 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

Official description

CFITSIO through 4.7.0 contains a heap-based out-of-bounds read vulnerability in the HCOMPRESS tile decoder that allows attackers to read past the compressed tile buffer via input_nnybble in fits_hdecompress.c. Attackers can supply a crafted FITS file with ZCMPTYPE HCOMPRESS_1 declaring oversized tile geometry to crash applications calling fits_read_pix or disclose limited heap memory.

Weakness: CWE-125

Which versions are affected by CVE-2026-111125?

It affects 1 product.

Products include Nasa Cfitsio.

How do I fix CVE-2026-111125?

Upgrade to a fixed version.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2026-111125 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-111125 exists.

Sources

Also known as AZL-108257, DEBIAN-CVE-2026-111125, ECHO-e938-c88b-d500, GHSA-98rm-rv63-xf58, UBUNTU-CVE-2026-111125.