What is CVE-2026-51807?

CVE-2026-51807 is a critical-severity vulnerability in N/a, classified under Stack-based Buffer Overflow. CVSS score: 9.8/10. Published 2026-07-14.

How severe is CVE-2026-51807?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Buffer overflow in N/a

CVE-2026-51807

Heap-based out-of-bounds write in j2k_precinct_subband::parse_packet_header() in OpenHTJ2K versions 0.18.3 and earlier (fixed in v0.18.4) caused by missing bounds validation before coding-pass lengths are written to j2k_codeblock::pass_length[128]. A crafted JPEG 2000 codestream containing malformed PPM packet headers can trigger a heap-based out-of-bounds write in j2k_precinct_subband::parse_packet_header() in source/core/coding/coding_units.cpp due to missing bounds validation for the j2k_codeblock::pass_length[128] array which can lead to heap corruption and process termination.

Vulnerability class: Buffer Overflow

EPSS: 0.007 (49.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

N/a — versions n/a

Weakness classification (CWE)

CWE-121 — Stack-based Buffer Overflow

References

Frequently asked questions

What is CVE-2026-51807?: CVE-2026-51807 is a critical-severity vulnerability in N/a, classified under Stack-based Buffer Overflow. CVSS score: 9.8/10. Published 2026-07-14.
How severe is CVE-2026-51807?: Critical severity. CVSS v3 base score is 9.8 out of 10.