CVE-2026-29135: CWE-20 Improper Input Validation in SEPPmail Secure Email Gateway
CVE-2026-29135 is a medium severity vulnerability in SEPPmail Secure Email Gateway versions before 15. 0. 3. It involves improper input validation where an attacker can craft a password-tag that bypasses subject sanitization. This could potentially allow manipulation of email subjects in ways not intended by the system. The vulnerability has a CVSS 4. 0 base score of 5. 3, indicating a moderate risk. There are no known exploits in the wild and no official patch information provided yet.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-29135) affects SEPPmail Secure Email Gateway prior to version 15.0.3. It is caused by improper input validation (CWE-20) allowing an attacker to craft a password-tag that bypasses the sanitization process applied to email subjects. This could lead to unexpected behavior in how email subjects are processed or displayed. The CVSS 4.0 vector indicates network attack vector, low attack complexity, no privileges required, user interaction required, and low impact on confidentiality and integrity, with low scope and no availability impact.
Potential Impact
The impact is moderate as the vulnerability allows bypassing subject sanitization, which may lead to manipulation of email subjects. This could potentially be used to deceive users or interfere with email processing. However, there is no indication of privilege escalation, data disclosure, or system compromise. No known exploits are reported in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official patch or fix information is provided, users should monitor SEPPmail advisories for updates. Until a fix is available, cautious handling of email subjects and awareness of this issue is advised.
CVE-2026-29135: CWE-20 Improper Input Validation in SEPPmail Secure Email Gateway
Description
CVE-2026-29135 is a medium severity vulnerability in SEPPmail Secure Email Gateway versions before 15. 0. 3. It involves improper input validation where an attacker can craft a password-tag that bypasses subject sanitization. This could potentially allow manipulation of email subjects in ways not intended by the system. The vulnerability has a CVSS 4. 0 base score of 5. 3, indicating a moderate risk. There are no known exploits in the wild and no official patch information provided yet.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-29135) affects SEPPmail Secure Email Gateway prior to version 15.0.3. It is caused by improper input validation (CWE-20) allowing an attacker to craft a password-tag that bypasses the sanitization process applied to email subjects. This could lead to unexpected behavior in how email subjects are processed or displayed. The CVSS 4.0 vector indicates network attack vector, low attack complexity, no privileges required, user interaction required, and low impact on confidentiality and integrity, with low scope and no availability impact.
Potential Impact
The impact is moderate as the vulnerability allows bypassing subject sanitization, which may lead to manipulation of email subjects. This could potentially be used to deceive users or interfere with email processing. However, there is no indication of privilege escalation, data disclosure, or system compromise. No known exploits are reported in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official patch or fix information is provided, users should monitor SEPPmail advisories for updates. Until a fix is available, cautious handling of email subjects and awareness of this issue is advised.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- NCSC.ch
- Date Reserved
- 2026-03-04T09:08:03.277Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 69ce2afae6bfc5ba1dc065e6
Added to database: 4/2/2026, 8:38:18 AM
Last enriched: 4/10/2026, 12:07:42 AM
Last updated: 5/20/2026, 8:51:37 PM
Views: 57
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