Description
In Exim before 4.99.2, when JSON lookup is enabled, an out-of-bounds heap write can occur when a JSON operator encounters malformed JSON in an untrusted header, because of an incorrect implementation of \ skipping.
References
- www.cve.org/CVERecord ↗
- nvd.nist.gov/vuln/detail/CVE-2026-40685 ↗
- code.exim.org/exim/exim/commit/9fdc057e71b87c87a0d3d2288b2810a0efaaba57 ↗
- exim.org/static/doc/security/CVE-2026-40685.txt ↗
- exim.org/static/doc/security/cve-2026-04.1/CVE2026-40685.assessment ↗
- www.openwall.com/lists/oss-security/2026/04/30/21 ↗
Related CVEs
← CVE Index: search every CVE from the last 30 days
This product uses the NVD API but is not endorsed or certified by the NVD. CVSS scores do not establish exploitation.