{"schemaVersion":3,"id":"CVE-2026-44638","aliases":["UBUNTU-CVE-2026-44638","DEBIAN-CVE-2026-44638"],"status":"published","duplicateOf":null,"title":null,"description":"libsixel is a SIXEL encoder/decoder implementation derived from kmiya's sixel. From  to 1.8.7-r1, a wrong NULL check after an allocation call in sixel_decode_raw and sixel_decode causes a NULL pointer dereference whenever the allocation fails. The check tests the address of the output parameter (always non-NULL) instead of the value the malloc returned. On allocation failure, the function continues and writes through a NULL pointer, crashing the process. This is a denial of service against any caller of these public APIs that hits a low-memory condition. 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