Review reviewHigh
CVE-2026-66141
Exim
Exim before 4.99.5 allows .forward privilege escalation because force_command for a pipe transport is mishandled.
- CVSS
- 7.4
- EPSS
- - - percentile
- CISA KEV
- Not listed
- Published
- 2026.07.24
Review review
The CVSS severity warrants an early asset and exposure review.
Known exploitationNot established by KEV
Exploit probability-
Technical severityCVSS 7.4
Vulnerability overview
Exim before 4.99.5 allows .forward privilege escalation because force_command for a pipe transport is mishandled.
Affected product and versions
- Product
- Exim
- Affected versions
- >= 4.82 < 4.99.5
- Fixed versions
- No verified fixed-version field is available yet
Recommended response sequence
Confirm exposure before applying a vendor-supported change.
- 1Identify
Confirm that Exim and an affected version are present.
- 2Prioritize
Combine exploitation signals with asset exposure and business criticality.
- 3Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
- 4Verify
Recheck the version, service health, access paths, and relevant logs.
Technical data
- CVSS vector
- CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
- CWE
- CWE-829