EIP-2026-103109

PRE-CVE

Exim 4.43 - 'auth_spa_server()' Remote

Title source: legacy
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for EIP-2026-103109. PoCs published by Yuri Gushin.

AI-analyzed exploit summary This exploit targets a buffer overflow vulnerability in Exim's SPA authentication (CVE-2026-103107) by sending a maliciously crafted base64-encoded payload to overflow a fixed-size buffer in `spa_base64_to_bits()`. It includes shellcode for a reverse shell and supports bruteforce targeting.

Description

Exim 4.43 - 'auth_spa_server()' Remote

Exploits (1)

exploitdb WORKING POC VERIFIED
by Yuri Gushin · cremotelinux
https://www.exploit-db.com/exploits/812

This exploit targets a buffer overflow vulnerability in Exim's SPA authentication (CVE-2026-103107) by sending a maliciously crafted base64-encoded payload to overflow a fixed-size buffer in `spa_base64_to_bits()`. It includes shellcode for a reverse shell and supports bruteforce targeting.

Classification
Working Poc 95%
Attack Type
Rce
Complexity
Moderate
Reliability
Reliable
Target: Exim <= 4.43
No auth needed
Prerequisites: Network access to Exim SMTP port (default 25) · Exim version <= 4.43 with SPA authentication enabled
devstral-2 · analyzed Feb 16, 2026 Full analysis →

Details

Status pre_cve
Tracked Since Feb 18, 2026