CVE-2023-22515: Atlassian Confluence Data Center and Server

Should you act?

Exploited: patch now if you run it

CISA has confirmed exploitation in the wild. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

Yes, if you run Atlassian Confluence Data Center and Server. CISA added this CVE to its Known Exploited Vulnerabilities catalog on 2023-10-05, which means there is reliable evidence of exploitation in the wild. US federal agencies must remediate by 2023-10-13; treat that as the outer limit, not the target. CISA also lists it as known to be used in ransomware campaigns.
EPSS 99.2%, percentile 99.9: FIRST’s model estimates a 99.2% chance of exploitation activity in the next 30 days, higher than 99.9% of all scored CVEs (very high). EPSS is a probability, not a verdict.
Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.

What it is

Atlassian has been made aware of an issue reported by a handful of customers where external attackers may have exploited a previously unknown vulnerability in publicly accessible Confluence Data Center and Server instances to create unauthorized Confluence administrator accounts and access Confluence instances. Atlassian Cloud sites are not affected by this vulnerability. If your Confluence site is accessed via an atlassian.net domain, it is hosted by Atlassian and is not vulnerable to this issue.

CISA’s summary

Atlassian Confluence Data Center and Server contains a broken access control vulnerability that allows an attacker to create unauthorized Confluence administrator accounts and access Confluence.

Weakness type: CWE-20.

Product: Atlassian Confluence Data Center and Server · Assigned by: atlassian · Published: 2023-10-04

Affected and fixed versions

Vendor	Product	Affected versions (per CVE record)
Atlassian	Confluence Data Center	>= 8.0.0, >= 8.0.1, >= 8.0.2, >= 8.0.3, >= 8.1.3, >= 8.1.4, >= 8.2.0, >= 8.2.1, >= 8.2.2, >= 8.2.3, >= 8.3.0, >= 8.3.1
Atlassian	Confluence Server	>= 8.0.0, >= 8.0.1, >= 8.0.2, >= 8.0.3, >= 8.1.3, >= 8.1.4, >= 8.2.0, >= 8.2.1, >= 8.2.2, >= 8.2.3, >= 8.3.0, >= 8.3.1

Severity scores

Scored by	CVSS	Score	Vector
atlassian	3.0	10 Critical	`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H`

Attack vector: network (remotely reachable)
Attack complexity: low
Privileges required: none (no login)
User interaction: none
Scope: changed (can affect other components)

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

CISA KEV: added 2023-10-05; federal due date 2023-10-13. Known ransomware use: Known.
CISA required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. Check all affected Confluence instances for evidence of compromise per vendor instructions and report any positive findings to CISA.
CISA SSVC assessment: exploitation active, automatable yes, technical impact total.
FIRST EPSS (model of 2026-10-21): 99.22% probability of exploitation activity in the next 30 days; percentile 99.9.

Timeline

2023-10-04 — CVE record published by atlassian
2023-10-05 — Added to CISA’s Known Exploited Vulnerabilities catalog
2023-10-13 — CISA remediation deadline for US federal agencies
2026-03-25 — CVE record last updated

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Other references from the CVE record and advisory

packetstormsecurity.com packetstormsecurity.com
confluence.atlassian.com confluence.atlassian.com
confluence.atlassian.com confluence.atlassian.com
jira.atlassian.com jira.atlassian.com

All exploited Atlassian vulnerabilities · Today’s Security Digest