Description
In Exim before 4.99.2, when utf8 operators are enabled, there is an out-of-bounds read if large UTF-8 trailing characters are present (malformed UTF-8 header data). Information might be divulged within an error message produced during handling of an unrelated e-mail message.
Published: 2026-04-30
Score: 3.7 Low
EPSS: < 1% Very Low
KEV: No
Impact: n/a
Action: n/a
AI Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

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Advisories
Source ID Title
Debian DSA Debian DSA DSA-6265-1 exim4 security update
Ubuntu USN Ubuntu USN USN-8228-1 Exim vulnerabilities
History

Fri, 01 May 2026 15:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Fri, 01 May 2026 02:30:00 +0000

Type Values Removed Values Added
References

Fri, 01 May 2026 02:00:00 +0000

Type Values Removed Values Added
References

Thu, 30 Apr 2026 21:45:00 +0000

Type Values Removed Values Added
Description In Exim before 4.99.2, when utf8 operators are enabled, there is an out-of-bounds read if large UTF-8 trailing characters are present (malformed UTF-8 header data). Information might be divulged within an error message produced during handling of an unrelated e-mail message.
First Time appeared Exim
Exim exim
Weaknesses CWE-125
CPEs cpe:2.3:a:exim:exim:*:*:*:*:*:*:*:*
Vendors & Products Exim
Exim exim
References
Metrics cvssV3_1

{'score': 3.7, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: mitre

Published:

Updated: 2026-05-01T14:27:11.390Z

Reserved: 2026-04-14T00:00:00.000Z

Link: CVE-2026-40686

cve-icon Vulnrichment

Updated: 2026-05-01T14:27:06.850Z

cve-icon NVD

Status : Analyzed

Published: 2026-04-30T22:16:25.787

Modified: 2026-05-01T17:44:15.677

Link: CVE-2026-40686

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-04-30T22:30:02Z

Weaknesses