PatchTheCVECVE-2025-67896: Exim before 4.99.1, with certain non-default rate-limit configurations, allows a remote heap-based buffer over
CVE-2025-67896 is a high-severity flaw (CVSS 7.0) affecting exim. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
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 this priority
- High severity
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 7.0 (High) |
| Attack vector | Network (remote) |
| Attack complexity | High |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.5% (top 59%) |
| CISA exploited list | No |
| Weakness | CWE-122 |
| Published | 2025-12-14 |
| Last modified | 2026-10-14 |
Last updated 2026-10-14 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Advisories and coverage
Official advisories
- Exim Announce: exim-4.99.1 2025-12-14
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2025-67896?
exim: upgrade to 4.99.1. Exact commands for each OS are on this page.
Is CVE-2025-67896 being exploited?
CVE-2025-67896 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2025-67896 affect?
CVE-2025-67896 affects exim. Severity is high (CVSS 7.0). 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.
How urgent is CVE-2025-67896?
Priority 40/100. High severity; Remotely exploitable, no login, no user action
Software pages
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