cfitsio vulnerability

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.

Published 15 Oct 2026Updated 20 Oct 20267 sources
CVSS 6.9 ✓ VERIFIED REFERENCE

What happened

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.

Affected versions

cfitsio: 0 through 4.7.0 (semver) Fixed: See vendor advisory.

Why it matters

Review the vendor advisory and exposure of the affected product to determine operational impact.

Detection & mitigation

  • Apply vendor-provided updates or mitigations.
  • Review affected product exposure and access logs.

Public PoC references

RepositoryAuthorFirst seenReference
hackmd.ioNVD reference2026-10-15Verified