CVE-2026-44638

Summary

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.

Affected Software

VendorProductVersion RangeStatus
saitohalibsixel>= 1.0.0, < 1.8.7-r2affected

Weaknesses

  • CWE-476: CWE-476: NULL Pointer Dereference
  • CWE-690: CWE-690: Unchecked Return Value to NULL Pointer Dereference

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: poc
    • Automatable: no
    • Technical Impact: partial

Additional References

References