Pillow is a Python imaging library. Versions 10.3.0 through 12.1.1 did not limit the amount of GZIP-compressed data read when decoding a FITS image, making them vulnerable to decompression bomb attacks. A specially crafted FITS file could cause unbounded memory consumption, leading to denial of service (OOM crash or severe performance degradation).
If users are unable to immediately upgrade, they should only open specific image formats, excluding FITS, as a workaround.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
High
Complete denial of service
CVSS Vector v4.0
Weakness Type (CWE)
References 4
https://github.com/python-pillow/Pillow/commit/3cb854e8b2bab43f40e342e665f9340d…
security-advisories@github.com
https://github.com/python-pillow/Pillow/pull/9521
security-advisories@github.com
https://github.com/python-pillow/Pillow/security/advisories/GHSA-whj4-6x5x-4v2j
security-advisories@github.com
https://pillow.readthedocs.io/en/stable/releasenotes/12.2.0.html#prevent-fits-d…
security-advisories@github.com