CVERadar
CRITICAL · CVSS 3.1 9.8CISA KEV · added 2023-11-07Metasploit modulePublic PoCKnown ransomware useEPSS 100.00% (p100)Threat level 99

CVE-2023-22518: Atlassian Confluence Data Center and Server Improper Authorization Vulnerability

Atlassian · Confluence Data Center and Server · NVD published 2023-10-31 · posted 2026-10-21 · last modified 2026-06-17

What it is

All versions of Confluence Data Center and Server are affected by this unexploited vulnerability. This Improper Authorization vulnerability allows an unauthenticated attacker to reset Confluence and create a Confluence instance administrator account. Using this account, an attacker can then perform all administrative actions that are available to Confluence instance administrator leading to - but not limited to - full loss of confidentiality, integrity and availability.  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.

WeaknessCWE-863
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H (source: [email protected])
CISA due date2023-11-28 (for US federal agencies under BOD; a good deadline for everyone)
ATT&CK tacticsInitial Access → Discovery → Command and Control

Exploitation evidence

First exploit evidence seen: 2023-10-31 (earliest date across the sources below).

Exploited in the wild

  • CISA KEV: listed since 2023-11-07. Source

Public exploit code

Metasploit

GitHub proof-of-concept repositories

8 public repositories from 8 accounts, first seen 2023-10-31. Most starred: ForceFledgling/CVE-2023-22518 (61 stars), view repository.

Verify before running: public PoCs can be malicious. Read the code and only run it in an isolated lab. A PoC means exploit code is public, not that this CVE is exploited in the wild.

Sources: CISA KEV · Rapid7 Metasploit Framework module metadata · nomi-sec/PoC-in-GitHub.

Defend the Chain

The attack chain for CVE-2023-22518 laid across the MITRE ATT&CK Enterprise tactics. Solid cards come from the MITRE CTID KEV mappings; dashed cards are inferred by CVERadar from the CWE or description. Correct defences are real ATT&CK mitigations for that technique.

Threat level 99/100
Defender level 1 · 0 XP
Chain links broken: 0/3

Reconnaissance

Resource Development

Initial Access

Execution

Persistence

Privilege Escalation

Stealth

Defense Impairment

Credential Access

Discovery

Lateral Movement

Collection

Command and Control

Exfiltration

Impact

Pick a red technique card on the board, then choose the defence that stops it.

Defend against T1190 Exploit Public-Facing Application CTID: exploitation technique

CVE-2023-22518 is an improper authorization vulnerability. Adversaries have been seen using HTTP POST requests to upload maliciously-crafted zip files to Confluence WebServers to exploit this vulnerability. After exploitation, adversaries were observed doing local system information discovery and downloading malicious payloads.

How to fix it

CISA required action

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. (source: CISA KEV)

Fixed versions

  • atlassian confluence data center: upgrade to 7.19.16 or later (affected from 1.0)
  • atlassian confluence data center: upgrade to 8.3.4 or later (affected from 7.20.0)
  • atlassian confluence data center: upgrade to 8.4.4 or later (affected from 8.4.0)
  • atlassian confluence data center: upgrade to 8.5.3 or later (affected from 8.5.0)
  • atlassian confluence server: upgrade to 7.19.16 or later (affected from 1.0)
  • atlassian confluence server: upgrade to 8.3.4 or later (affected from 7.20.0)
  • atlassian confluence server: upgrade to 8.4.4 or later (affected from 8.4.0)
  • atlassian confluence server: upgrade to 8.5.3 or later (affected from 8.5.0)

Derived from the NVD CPE configuration (versionEndExcluding / versionEndIncluding). Always confirm with the vendor advisory.

Vendor advisories and patches

MITRE ATT&CK mitigations for this chain

  • M1048 Application Isolation and Sandboxing (for T1190) : Application isolation will limit what other processes and system features the exploited target can access.
  • M1037 Filter Network Traffic (for T1190, T1105) : Restrict outbound network traffic from public-facing servers to prevent unauthorized connections from initiating communications with attacker-controlled infrastructure. While this may not prevent the initial exploitation, it limits the attacker's ability to verify and control the compromised server post-exploit, reduci
  • M1030 Network Segmentation (for T1190) : Segment externally facing servers and services from the rest of the network with a DMZ or on separate hosting infrastructure.
  • M1016 Vulnerability Scanning (for T1190) : Regularly scan externally facing systems for vulnerabilities and establish procedures to rapidly patch systems when critical vulnerabilities are discovered through scanning and through public disclosure.
  • M1026 Privileged Account Management (for T1190) : Use least privilege for service accounts will limit what permissions the exploited process gets on the rest of the system.
  • M1050 Exploit Protection (for T1190) : Web Application Firewalls may be used to limit exposure of applications to prevent exploit traffic from reaching the application.
  • M1035 Limit Access to Resource Over Network (for T1190) : Ensure that all publicly exposed services are actually intended to be so, and restrict access to any that should only be available internally.
  • M1051 Update Software (for T1190) : Update software regularly by employing patch management for externally exposed applications.
  • M1031 Network Intrusion Prevention (for T1105) : Network intrusion detection and prevention systems that use network signatures to identify traffic for specific adversary malware or unusual data transfer over known protocols like FTP can be used to mitigate activity at the network level. Signatures are often for unique indicators within protocols and may be based on

Detection Generic guidance

  • Initial Access: Alert on unusual requests to the affected service (odd paths, oversized payloads, exploit strings) in WAF, reverse-proxy and application logs.
  • Discovery: Look for directory listing, file enumeration and reconnaissance commands from service accounts.
  • Command and Control: Alert on outbound connections from the server to new or rare destinations.

Response checklist Generic guidance

  1. Inventory: find every instance of the affected product and version (include internet-facing and forgotten ones).
  2. Patch or mitigate per the vendor advisory; if you cannot patch, remove internet exposure or apply the vendor workaround.
  3. Assume compromise if the system was exposed before patching: hunt for the indicators in the advisory and review logs back to the disclosure date.
  4. Rotate credentials and secrets stored on or used by the affected system if compromise cannot be ruled out.

Sources