Exploited vulnerability · CISA KEV
Yes. CVE-2023-34192, Synacor Zimbra Collaboration Suite (ZCS) Cross-Site Scripting (XSS) Vulnerability, is being exploited in the wild. CISA added it to its Known Exploited Vulnerabilities catalog on 25 Feb 2025, 600 days after it was published. It affects Synacor Zimbra Collaboration Suite (ZCS). If you run it, CISA's required action is: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Synacor Zimbra Collaboration Suite (ZCS) contains a cross-site scripting (XSS) vulnerability that allows a remote authenticated attacker to execute arbitrary code via a crafted script to the /h/autoSaveDraft function.
| Vendor | Synacor (19 exploited CVEs in KEV) |
| Product | Zimbra Collaboration Suite (ZCS) |
| Vulnerability | Synacor Zimbra Collaboration Suite (ZCS) Cross-Site Scripting (XSS) Vulnerability |
| Weakness | CWE-79 |
| Published | 6 Jul 2023 |
| Added to KEV | 25 Feb 2025 |
| Reported by (CNA) | mitre |
Yes. CISA added CVE-2023-34192 to the Known Exploited Vulnerabilities catalog on 25 Feb 2025, which means there is reliable evidence of exploitation in the wild.
CISA does not list known ransomware use for it. That can change, and exploitation alone is reason to fix it first.
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. Check Synacor's advisory for the fixed versions, and if you can't patch quickly, restrict access to the affected Zimbra Collaboration Suite (ZCS) and watch it for signs of compromise.
Sources: CISA KEV (exploitation, ransomware use, required action, due date), the CVE record (publication date, CVSS, CNA), NVD and FIRST EPSS (live score). More: all KEV additions in February 2025 · Synacor scorecard · act-now radar.
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