Use After Free Affecting exim/exim package, versions [,4.99.3)
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-16670040
- published14 May 2026
- disclosed12 May 2026
- creditUnknown
Introduced: 12 May 2026
CVE-2026-45185 (opens in a new tab)How to fix?
Upgrade exim/exim to version 4.99.3 or higher.
Overview
Affected versions of this package are vulnerable to Use After Free in the BDAT body parsing process when a client sends a TLS close_notify mid-body during a CHUNKING transfer, followed by a final cleartext byte on the same TCP connection. An attacker can achieve heap corruption and potentially execute arbitrary code by exploiting this sequence remotely over the network. This is only exploitable if GnuTLS is configured and the specific sequence of TLS and cleartext data is received during a CHUNKING transfer.