CVE-2026-44638
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. This vulnerability is fixed in 1.8.7-r2.
Scoring
- Severity
- LOW
- CVSS base score
- 2.5
- CVSS vector
- CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:L
- EPSS probability
- 0.13%
- CWE
- CWE-476, CWE-690
- Published
- 2026-05-14
- Last modified
- 2026-05-15
Affected products
- saitoha libsixel
Weakness type
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