CVE-2023-26430
Attackers with access to user accounts can inject arbitrary control characters to SIEVE mail-filter rules.
Does this matter?
Lower severity and a low EPSS score (0.75%). Track it; it rarely justifies an emergency change on its own.
Description
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.
- CVSS 3.1
- 4.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
- EPSS
- 0.75% probability · 54th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-77
- Affected
- open-xchange/open-xchange appsuite backend
- Source
- security@open-xchange.com
EPSS 0.8% since 8 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://packetstormsecurity.com/files/173943/OX-App-Suite-SSRF-SQL-Injection-Cross-Site-Scripting.htmlThird Party Advisory, VDB Entry
- http://seclists.org/fulldisclosure/2023/Aug/8Mailing List, Third Party Advisory
- https://documentation.open-xchange.com/appsuite/security/advisories/csaf/2023/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.pdfRelease Notes
- http://packetstormsecurity.com/files/173943/OX-App-Suite-SSRF-SQL-Injection-Cross-Site-Scripting.htmlThird Party Advisory, VDB Entry
- http://seclists.org/fulldisclosure/2023/Aug/8Mailing List, Third Party Advisory
- https://documentation.open-xchange.com/appsuite/security/advisories/csaf/2023/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.pdfRelease Notes
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.