Bug 2504503 (CVE-2026-47667)

Summary: CVE-2026-47667 CImg: CImg Library: Denial of service due to unbounded memory allocation in image file processing.
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
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Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in the CImg Library, a C++ library for image processing. This vulnerability allows a remote attacker to cause a denial of service (DoS) by providing a specially crafted image file. The library incorrectly handles the header size when processing Analyze/NIfTI files, leading to excessive memory allocation and subsequent memory leaks. This can exhaust system resources, making the application unavailable.
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Bug Depends On: 2506062, 2506063, 2506064, 2506065    
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Description OSIDB Bzimport 2026-07-21 21:03:10 UTC 
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.