Bug 2450768 (CVE-2026-4775)

Summary: CVE-2026-4775 libtiff: libtiff: Arbitrary code execution or denial of service via signed integer overflow in TIFF file processing
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in the libtiff library. A remote attacker could exploit a signed integer overflow vulnerability in the putcontig8bitYCbCr44tile function by providing a specially crafted TIFF file. This flaw can lead to an out-of-bounds heap write due to incorrect memory pointer calculations, potentially causing a denial of service (application crash) or arbitrary code execution.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2450769, 2450770, 2450771, 2450772, 2450773    
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Description OSIDB Bzimport 2026-03-24 14:34:15 UTC 
A flaw was found in the libtiff library. A signed integer overflow exists in the putcontig8bitYCbCr44tile function (and potentially similar functions like putcontig8bitYCbCr42tile, putcontig8bitYCbCr22tile, and putcontig8bitYCbCr12tile) within tif_getimage.c. When processing a specially crafted TIFF file with an extremely large width and specific YCbCr subsampling, the calculation for the pointer progression variable (incr) can overflow the 32-bit signed integer boundary. This results in an incorrect negative progression of memory pointers, leading to an out-of-bounds heap write. An attacker could exploit this to cause a denial of service (application crash) or potentially execute arbitrary code.