Authorization bypass in MailWatch lets users alter other users' mail
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- None · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-639.
Summary
MailWatch for MailScanner before 1.2.27 is affected. An authenticated user can release to inbox or permanently delete quarantined mail belonging to other users or domains by supplying an arbitrary message identifier, because ownership of the message is never checked (CWE-639). Message identifiers can be enumerated, so a low-privilege user can force delivery of held mail or destroy it.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
Description from the CNA
MailWatch for MailScanner is a web-based front-end to MailScanner. Prior to 1.2.27, any authenticated MailWatch user, including the U/user, D/domain-admin, and H/host roles, can release to inbox or permanently delete the quarantined mail of any other user or domain by supplying an arbitrary message `id` to `mailscanner/quarantine_action.php`. The action path calls `quarantine_list_items()` in `mailscanner/functions.php`, which selects from `maillog` by the supplied identifier without the per-role `global_filter` applied by listing and read views. The action requires a valid session and CSRF token, but the caller can submit a token from the caller's own session; ownership of the requested message is never checked. Message identifiers are enumerable, allowing a low-privilege user to invoke `quarantine_release()` or `quarantine_delete()` for other users' or domains' quarantined messages, force-delivering mail held by the quarantine or permanently deleting it. This issue is fixed in version 1.2.27.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
Remediation
Upgrade MailWatch for MailScanner to version 1.2.27, which fixes this issue.
Written with Claude Haiku 5.5 from the sources below · 2026-10-29
- Fix · CNA MailWatch (mailwatch) Fixed in 1.2.27
Timeline
- 2026-10-28 Threatist record created from CVE-2026-85749
- 2026-10-29 CISA SSVC decision points changed
- 2026-10-29 Priority changed: MEDIUM → HIGH
References
More mailwatch vulnerabilities
- TI-2008-05687 Directory traversal vulnerability in docs.php in MailWatch for MailScanner 1.0.4 and… CVSS 2.0HIGH 7.5
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences