CVE-2022-37042: in the CISA KEV catalogue
Synacor Zimbra Collaboration Suite (ZCS) Authentication Bypass Vulnerability. CISA added CVE-2022-37042 to the Known Exploited Vulnerabilities catalogue on 2022-08-11 with a default due date of 2022-09-01. Known ransomware campaign use: Known. Forensic triage flag: No.
Synacor Zimbra Collaboration Suite (ZCS) contains an authentication bypass vulnerability in MailboxImportServlet. This vulnerability was chained with CVE-2022-27925 which allows for unauthenticated remote code execution. (CISA description)
- Vendor / product
- Synacor Zimbra Collaboration Suite (ZCS)
- CWE
- CWE-23
- CISA required action
- Apply updates per vendor instructions.
- EPSS
- 92%, percentile 99 (scored 2026-11-03)
EPSS puts about 92 in 100 odds (92%) on exploitation activity being observed in the next 30 days. Its score is higher than or equal to that of 99% of scored CVEs. This is a model estimate about exploitation anywhere, not about your environment.
Vendor and reference links (from CISA)
Your own deadline under CISA BOD 26-04 depends on exposure, automatability and technical impact: work it out with the BOD 26-04 calculator.
Frequently asked questions
Is CVE-2022-37042 in the CISA KEV catalogue?
Yes. CISA added CVE-2022-37042 (Synacor Zimbra Collaboration Suite (ZCS) Authentication Bypass Vulnerability) to the Known Exploited Vulnerabilities catalogue on 2022-08-11. CISA's default due date for it is 2022-09-01.
Is CVE-2022-37042 used in ransomware attacks?
CISA marks known ransomware campaign use as Known for CVE-2022-37042.
What should I do about CVE-2022-37042?
CISA's required action: Apply updates per vendor instructions.
Sources
- CISA, Known Exploited Vulnerabilities Catalog (accessed 2026-11-03)
- FIRST, Exploit Prediction Scoring System (EPSS) (EPSS by FIRST; scores generated by Empirical Security)
- NVD record for CVE-2022-37042