SEPTEMBER 15, 2026
Live Feed
Back to database
Case File

CVE-2026-42007

CRITICAL · CVSS 9.1 EPSS 0.29% Public Exploit

Source: NVD + CISA KEV + EPSS · Published 2026-08-28 · Last synced 2026-09-15

CyberRota Analysis

AI-Generated

The vulnerability allows authenticated attackers to exploit a use-after-free condition in the mail editing code via a Sieve script with the editheader extension, potentially leading to memory corruption and arbitrary code execution during mail delivery. This critical flaw can crash the delivery process and compromise system integrity. Organizations using affected mail systems should prioritize immediate mitigation by disabling the Sieve editheader extension and updating to a secure version.

Public Exploit Signal

A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.

Detected Signals
exploit

Note: these links are listed for security research and verification purposes only.

CVE
CVE-2026-42007
Severity
CRITICAL
CVSS
9.1
EPSS
0.29%

Original NVD Description

An attacker that has valid credentials can use a Sieve script with the editheader extension to trigger a use-after-free in the mail editing code, and to write memory contents beyond the intended buffer into the delivered mail. This causes memory leak and opportunity to do memory corruption during mail delivery, which can crash the delivery process and may allow execution of arbitrary code in the context of that process. Disable the Sieve editheader extension. Update to non-vulnerable version. No publicly available exploits are known.