Out-of-bounds Read Affecting exim/exim package, versions [,4.99.2)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-UNMANAGED-EXIMEXIM-16325120
- published1 May 2026
- disclosed30 Apr 2026
- creditUnknown
Introduced: 30 Apr 2026
CVE-2026-40686 (opens in a new tab)How to fix?
Upgrade exim/exim to version 4.99.2 or higher.
Overview
Affected versions of this package are vulnerable to Out-of-bounds Read in the processing of UTF-8 data when utf8 operators are enabled and large trailing characters are present. An attacker can cause information disclosure by sending malformed UTF-8 header data, which may result in sensitive information being included in error messages.