CVE-2021-26085

Atlassian Confluence Server: Pre-Authorization Arbitrary File Read

As of , CVE-2021-26085 in Atlassian Confluence Server is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch this week.

Exploited
Yes: CISA listed it on 28 March 2022
US federal deadline
18 April 202221 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
Known
EPSS score
0.99Higher than 99% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
EPSS when listed
0.23 on 28 March 2022EPSS on the day CISA listed it.
Public exploit
1 Exploit-DB entry
Fix
No vendor link in CISA's entry

What CISA says to do

Apply updates per vendor instructions.

CISA's required action

What the flaw is

Affected versions of Atlassian Confluence Server allow remote attackers to view restricted resources via a pre-authorization arbitrary file read vulnerability in the /s/ endpoint.

CISA's description

Affected versions of Atlassian Confluence Server allow remote attackers to view restricted resources via a Pre-Authorization Arbitrary File Read vulnerability in the /s/ endpoint. The affected versions are before version 7.4.10, and from version 7.5.0 before 7.12.3.

The CVE record's description, from atlassian

CVE published
3 August 2021
Assigned by
atlassian
CVSS
5.3 Medium (CVSS 3.1, from CISA-ADP)
CWE-425
Direct Request ('Forced Browsing')
CISA SSVC, exploitation
active
CISA SSVC, automatable
yes
CISA SSVC, technical impact
partial

Timeline

  1. The CVE record was published.
  2. Exploit-DB published an exploit (EDB-ID 50377).
  3. CISA added it to its list of exploited vulnerabilities.
  4. The US federal deadline to fix it.

Public exploits

Facts from Metasploit's module list and Exploit-DB's index; we never copy exploit code.

Read further