CVE-2026-1837
A specially-crafted file can cause libjxl's decoder to write pixel data to uninitialized unallocated memory.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.29%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
A specially-crafted file can cause libjxl's decoder to write pixel data to uninitialized unallocated memory. Soon after that data from another uninitialized unallocated region is copied to pixel data. This can be done by requesting color transformation of grayscale images to another grayscale color space. Buffers allocated for 1-float-per-pixel are used as if they are allocated for 3-float-per-pixel. That happens only if LCMS2 is used as CMS engine. There is another CMS engine available (selected by build flags).
- CVSS 4.0
- 8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
- EPSS
- 0.29% probability · 21th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-805, CWE-770, CWE-787
- Affected
- libjxl project/libjxl
- Source
- cve-coordination@google.com
References
- https://github.com/libjxl/libjxl/issues/4549Exploit, Issue Tracking, Patch
- https://access.redhat.com/security/cve/CVE-2026-1837
- https://bugzilla.redhat.com/show_bug.cgi?id=2438974
- https://github.com/libjxl/libjxl/issues/4549Exploit, Issue Tracking, Patch
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-1837.json
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.