Attackers with access to user accounts can inject arbitrary control characters to SIEVE mail-filter rules. This could be abused to access SIEVE extension that are not allowed by App Suite or to inject rules which would break per-user filter processing, requiring manual cleanup of such rules. We have added sanitization to all mail-filter APIs to avoid forwardning control characters to subsystems. No publicly available exploits are known.

References

• https://nvd.nist.gov/vuln/detail/CVE-2023-26430
• https://documentation.open-xchange.com/security/advisories/csaf/oxas-adv-2023-0003.json
• https://software.open-xchange.com/products/appsuite/doc/Release_Notes_for_Patch_Release_6230_7.10.6_2023-05-02.pdf
• http://seclists.org/fulldisclosure/2023/Aug/8
• http://packetstormsecurity.com/files/173943/OX-App-Suite-SSRF-SQL-Injection-Cross-Site-Scripting.html
• https://documentation.open-xchange.com/appsuite/security/advisories/csaf/2023/oxas-adv-2023-0003.json