LDAP Injection Affecting maddy package, versions <0.9.3-r0
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-ALPINE324-MADDY-17301438
- published11 Jun 2026
- disclosed16 Apr 2026
Introduced: 16 Apr 2026
CVE-2026-40193 (opens in a new tab)How to fix?
Upgrade Alpine:3.24 maddy to version 0.9.3-r0 or higher.
NVD Description
Note: Versions mentioned in the description apply only to the upstream maddy package and not the maddy package as distributed by Alpine.
See How to fix? for Alpine:3.24 relevant fixed versions and status.
maddy is a composable, all-in-one mail server. Versions prior to 0.9.3 contain an LDAP injection vulnerability in the auth.ldap module where user-supplied usernames are interpolated into LDAP search filters and DN strings via strings.ReplaceAll() without any LDAP filter escaping, despite the go-ldap/ldap/v3 library's ldap.EscapeFilter() function being available in the same import. This affects three code paths: the Lookup() filter, the AuthPlain() DN template, and the AuthPlain() filter. An attacker with network access to the SMTP submission or IMAP interface can inject arbitrary LDAP filter expressions through the username field in AUTH PLAIN or LOGIN commands. This enables identity spoofing by manipulating filter results to authenticate as another user, LDAP directory enumeration via wildcard filters, and blind extraction of LDAP attribute values using authentication responses as a boolean oracle or via timing side-channels between the two distinct failure paths. This issue has been fixed in version 0.9.3.