CVE-2023-22518: in the CISA KEV catalogue

Atlassian Confluence Data Center and Server Improper Authorization Vulnerability. CISA added CVE-2023-22518 to the Known Exploited Vulnerabilities catalogue on 2023-11-07 with a default due date of 2023-11-28. Known ransomware campaign use: Known. Forensic triage flag: No.

Atlassian Confluence Data Center and Server contain an improper authorization vulnerability that can result in significant data loss when exploited by an unauthenticated attacker. There is no impact on confidentiality since the attacker cannot exfiltrate any data. (CISA description)

Vendor / product: Atlassian Confluence Data Center and Server
CWE: CWE-863
CISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
EPSS: 100%, percentile 99 (scored 2026-11-03)

EPSS puts nearly every time in 100 odds (100%) 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.

Data dates. CISA KEV catalogue version 2026.11.03, released 2026-11-03, 1,767 entries (checked 2026-11-03). EPSS model v2026.06.15, scored 2026-11-03, 399,388 CVEs. Sources: CISA and FIRST (EPSS by FIRST; scores generated by Empirical Security). Copied to our own database and refreshed automatically; if a refresh fails, the previous copy keeps serving with its own date.

Frequently asked questions

Is CVE-2023-22518 in the CISA KEV catalogue?

Yes. CISA added CVE-2023-22518 (Atlassian Confluence Data Center and Server Improper Authorization Vulnerability) to the Known Exploited Vulnerabilities catalogue on 2023-11-07. CISA's default due date for it is 2023-11-28.

Is CVE-2023-22518 used in ransomware attacks?

CISA marks known ransomware campaign use as Known for CVE-2023-22518.

What should I do about CVE-2023-22518?

CISA's required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

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-2023-22518