TI-2025-41509 Aliases CVE-2025-67896 GHSA-6qxw-x3vc-phrg

Heap-based buffer overflow in Exim

MEDIUM 42CWE-122Published 2025-12-14 · Updated 2025-12-18

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Code execution
Confidentiality · integrity · availability: High · High · High
Fix status: Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-122 and the CVSS impact.

Summary

Exim before 4.99.1, with certain non-default rate-limit configurations, allows a remote heap-based buffer overflow because database records are cast directly to internal structures without validation.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.0047 40th percentileScored 2026-11-07

Fix Fixed Exim (Exim): 4.99.1

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Exim	Exim	4.99 to before 4.99.1	4.99.1	Patch available	CNA

Exim VendorExim Affected 4.99 to before 4.99.1 Fixed in 4.99.1 Patch available CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:exim:exim::::::::	before 4.99.1	Vulnerable	Exim

cpe:2.3:a:exim:exim:*:*:*:*:*:*:*:* Versions before 4.99.1 Vulnerable ·Exim

Remediation

Fix · CNA Exim (Exim) Fixed in 4.99.1

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product

Red Hat

Timeline

2026-10-02 Threatist record created from CVE-2025-67896
2026-10-03 Alias added: GHSA-6qxw-x3vc-phrg

References

Advisory 2

Other 1

https://www.openwall.com/lists/oss-security/2025/12/11/2

TI-2019-12627 Exim 4.92 through 4.92.2 allows remote code execution, a different vulnerability than… KEVCVSS 3.1CRITICAL 9.8
TI-2019-07471 OS command injection in exim KEVCVSS 3.1CRITICAL 9.8
TI-2018-04965 An issue was discovered in the base64d function in the SMTP listener in Exim before… KEVCVSS 3.1CRITICAL 9.8
TI-2010-04077 Heap-based buffer overflow in the string_vformat function in string.c in Exim before 4.70… KEVCVSS 3.1CRITICAL 9.8
TI-2010-04078 Exim 4.72 and earlier allows local users to gain privileges by leveraging the ability of… KEVCVSS 3.1HIGH 7.8
TI-2025-19707 SQL injection in Exim CVSS 3.1CRITICAL 9.8

See all 69 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences