---
cve: "CVE-2026-40685"
severity: "MEDIUM"
cvss: 6.5
epss: "32%"
vendor: "exim"
kev: false
exploited: false
published: "2026-04-30 22:16:25"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-15T06:51:19+02:00"
---

# CVE-2026-40685

> 6.5 MEDIUM

## Beschreibung

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.

## CVSS-Vektor

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

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Hoch | good |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Keine | good |
| I Integrität | Gering | warn |
| A Verfügbarkeit | Hoch | bad |

## Referenzen

- <https://www.openwall.com/lists/oss-security/2026/04/30/21>
- <https://exim.org/static/doc/security/cve-2026-04.1/CVE2026-40685.assessment>
- <https://code.exim.org/exim/exim/commit/9fdc057e71b87c87a0d3d2288b2810a0efaaba57>
- <https://exim.org/static/doc/security/CVE-2026-40685.txt>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-40685) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_