External service lookups for a number of protocols were vulnerable to a time-of-check/time-of-use (TOCTOU) weakness, involving the JDK DNS cache. Attackers that were timing DNS cache expiry correctly were able to inject configuration that would bypass existing network deny-lists. Attackers could exploit this weakness to discover the existence of restricted network infrastructure and service availability. Improvements were made to include deny-lists not only during the check of the provided connection data, but also during use. No publicly available exploits are known.

References

• https://nvd.nist.gov/vuln/detail/CVE-2023-26438
• 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
• https://documentation.open-xchange.com/appsuite/security/advisories/csaf/2023/oxas-adv-2023-0003.json
• http://packetstormsecurity.com/files/173943/OX-App-Suite-SSRF-SQL-Injection-Cross-Site-Scripting.html
• http://seclists.org/fulldisclosure/2023/Aug/8