{"api_version":"1","generated_at":"2026-04-23T16:55:58+00:00","cve":"CVE-2026-33020","urls":{"html":"https://cve.report/CVE-2026-33020","api":"https://cve.report/api/cve/CVE-2026-33020.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-33020","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-33020"},"summary":{"title":"libsixel: Integer Overflow in write_png_to_file() leads to Heap-based Buffer Overflow","description":"libsixel is a SIXEL encoder/decoder implementation derived from kmiya's sixel. Versions 1.8.7 and prior contain an integer overflow which leads to a heap buffer overflow via sixel_frame_convert_to_rgb888() in frame.c, where allocation size and pointer offset computations for palettised images (PAL1, PAL2, PAL4) are performed using int arithmetic before casting to size_t. 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