CVE-2026-40687: Critical severity Exim Exim vulnerability
In Exim before 4.99.2, when the SPA authentication driver is used with an adversarial SPA resource, there can be an out-of-bounds write that crashes the connection instance, or erroneous data processing that divulges data from uninitialized heap memory.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
alpine/eximto a version that resolves this vulnerability.Fixed in 4.98.2-r0
Event History
Frequently Asked Questions
What is the severity of CVE-2026-40687?
CVE-2026-40687 is considered a critical vulnerability due to its potential to crash connections and leak sensitive data.
How do I fix CVE-2026-40687?
To fix CVE-2026-40687, upgrade Exim to version 4.99.2 or later.
What software is affected by CVE-2026-40687?
CVE-2026-40687 affects Exim versions prior to 4.99.2.
What kind of vulnerability is CVE-2026-40687?
CVE-2026-40687 is an out-of-bounds write vulnerability that can lead to crashes or data leaks.
Is CVE-2026-40687 exploitable remotely?
Yes, CVE-2026-40687 can be exploited remotely through adversarial SPA resources.