CVE-2026-44638

low

Published 2026-05-14 · Modified 2026-05-15

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CVSS v3

2.5

CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:L

CVSS v4 NEW

—

not yet in upstream

VIR risk

2.5

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. This vulnerability is fixed in 1.8.7-r2.

Predictions

Exploit likelihood

27%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

OS impact

SUSE Affected 1 release

Version	Status	Fixed in
—	Affected	—

Debian Mixed 5 releases

Version	Status	Fixed in
trixie	Affected	—
sid	Fixed	`1:1.8.7-r2-1`
forky	Fixed	`1:1.8.7-r2-1`
bullseye	Affected	—
bookworm	Affected	—

Application impact

Vendor	Product	Versions	Fixed
saitoha	libsixel	`{"startIncluding":"1.0.0","endExcluding":"1.8.7-r2"}`	`1.8.7-r2`

References

CWEs

CWE-476 CWE-690

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.