CyberSecBulletin
CVE-2024-21683NVD status: Modified

Confluence Data Center: Improper Control of Generation of Code

Published Updated By the CyberSecBulletin desk

CVE-2024-21683 is a high-severity improper control of generation of code vulnerability in Confluence Data Center from Atlassian, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected Confluence Data Center versions: 8.9.0; 8.8.0 to 8.8.1; 8.7.1 to 8.7.2, and others listed below. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 88.3% chance of exploitation within 30 days, which is in the top 0.23% of all scored CVEs.

Patch now

Exploitation in the next 30 days is more likely than not, according to EPSS.

What to do

  1. Update Confluence Server to 7.19.24 or 8.5.11, whichever matches your release line, or a later version.
  2. Update Fisheye to 4.8.15 or a later version.
  3. Update Crucible to 4.8.15 or a later version.
  4. Read the advisory on confluence.atlassian.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
AtlassianConfluence Data Center8.9.0; 8.8.0 to 8.8.1; 8.7.1 to 8.7.2; 8.6.0 to 8.6.2; 8.5.0 to 8.5.8; 8.4.0 to 8.4.5; 8.3.0 to 8.3.4; 8.2.0 to 8.2.3; and 18 more rangesNot stated
AtlassianConfluence Server7.19.0 up to, but not including, 7.19.24; 7.20.0 through 7.20.3; 8.0.0 through 8.0.4; 8.1.0 through 8.1.4; 8.2.0 through 8.2.3; 8.3.0 through 8.3.4; 8.4.0 through 8.4.5; 8.5.0 up to, but not including, 8.5.11; and 6 more ranges7.19.24, 8.5.11
AtlassianFisheye4.8.0 up to, but not including, 4.8.154.8.15
AtlassianCrucible4.8.0 up to, but not including, 4.8.154.8.15
AtlassianJira Data Center9.4.0 up to, but not including, 9.4.21; 9.12.0 up to, but not including, 9.12.89.4.21, 9.12.8
AtlassianJira Server9.4.0 up to, but not including, 9.4.21; 9.12.0 up to, but not including, 9.12.89.4.21, 9.12.8
AtlassianJira Service Management5.4.0 up to, but not including, 5.4.21; 5.12.0 up to, but not including, 5.12.8; 5.15.2 up to, but not including, 5.16.0; 5.15.25.4.21, 5.12.8, 5.16.0

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.8HighCNA (atlassian.com)
CVSS 3.18.8HighNVD

Official description

This High severity RCE (Remote Code Execution) vulnerability was introduced in version 5.2 of Confluence Data Center and Server. This RCE (Remote Code Execution) vulnerability, with a CVSS Score of 7.2, allows an authenticated attacker to execute arbitrary code which has high impact to confidentiality, high impact to integrity, high impact to availability, and requires no user interaction. Atlassian recommends that Confluence Data Center and Server customers upgrade to latest version. If you are unable to do so, upgrade your instance to one of the specified supported fixed versions. See the release notes https://confluence.atlassian.com/doc/confluence-release-notes-327.html You can download the latest version of Confluence Data Center and Server from the download center https://www.atlassian.com/software/confluence/download-archives. This vulnerability was found internally.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Control of Generation of Code

The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.

How developers prevent this class of flaw

  • Refactor your program so that you do not have to dynamically generate code.
  • Run your code in a jail or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which code can be executed by your product. Examples include the Unix chroot jail and AppArmor. In general, managed code may provide some protection. This may not be a feasible solution, and it only limits the impact to the operating system; the rest of your application may still be subject to compromise. Be careful to avoid CWE-243 and other weaknesses related to jails.
  • Use dynamic tools and techniques that interact with the product using large test suites with many diverse inputs, such as fuzz testing (fuzzing), robustness testing, and fault injection. The product's operation may slow down, but it should not become unstable, crash, or generate incorrect results.

More Improper Control of Generation of Code vulnerabilities (CWE-94)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other references

Other vulnerabilities in Confluence Data Center

All Confluence Data Center vulnerabilities

Recent Improper Control of Generation of Code vulnerabilities

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