CVE-2026-47667
CImg Library is a C++ library for image processing. Prior to version 4.0.0 in `_load_analyze()`, the header_size field is read as an `unsigned int` from the first 4 bytes of an Analyze/NIfTI file and passed directly to `new unsigned char[header_size]` without being bounded against the actual file size. A value up to ~4 GB is accepted. If the subsequent `fread` returns `short` as it will for any malformed file), the function throws a `CImgIOException` and the allocated buffer is never freed. A 6-byte crafted file is sufficient to trigger an allocation of ~1.3 GB per call, with the full allocation leaked on every error path. The issue is reachable via `load_analyze()` and the generic `load()` when the file extension is .hdr, .img, or .nii. Version 4.0.0 fixes the issue.
What this means
- Exposure
- Exploitable remotely over the network, without authentication and with no action from the victim.
- Impact
- An attacker can take the service offline.
- Weakness
- Memory is never released, so consumption climbs until exhaustion.
- Likelihood
- Its EPSS score stays low: nothing points to imminent exploitation, which is no reason to leave it unpatched.
What to doFold into the next patch cycle. Start with the instances exposed to the internet.
Read automatically from the CVSS vector, the weakness type (CWE) and the EPSS score. The technical description above remains the one published by NIST.