# CVE-2020-17496: vBulletin - RCE

> Live exploitation tracking for CVE-2020-17496 by the CrowdSec Live Exploit Tracker, built from real-world attack data crowdsourced from CrowdSec's global network.

Page: https://tracker.crowdsec.net/cves/CVE-2020-17496

## Key facts

- **Exploitation phase:** Background Noise. Continuous low-level scanning or exploitation attempts are observed, mostly opportunistic and automated.
- **CVSS score:** 9.8
- **Public exploit available:** Yes
- **Affected products:** Jelsoft vBulletin
- **Weaknesses:** CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection'))
- **Tags:** web_application

## Description

vBulletin 5.5.4 through 5.6.2 allows remote command execution via crafted subWidgets data in an ajax/render/widget_tabbedcontainer_tab_panel request. NOTE: this issue exists because of an incomplete fix for CVE-2019-16759.

## CrowdSec analysis

[CVE-2020-17496](https://euvd.enisa.europa.eu/vulnerability/CVE-2020-17496) is a critical vulnerability in vBulletin that allows remote attackers to achieve unauthenticated command execution by abusing ajax functionality with specially crafted data.

CrowdSec has been tracking this vulnerability and its exploits since 15th of December 2023.

According to CrowdSec data, while opportunistic exploitation dominates, a portion of threat actors trying to exploit CVE-2020-17496 apply basic targeting methods such as port or service detection. This indicates emerging patterns of selective targeting.
Telemetry from the CrowdSec network also shows that exploitation activity for CVE-2020-17496 remains steady week-over-week. Attack volumes are consistent with long-term trends, indicating sustained interest from threat actors. CVE-2020-17496 continues to be an active part of the threat landscape and will likely remain this way for the forseeable future.

Attackers typically target URLs containing `/ajax/render/widget_tabbedcontainer_tab_panel` in their exploitation attempts.

## Timeline

- 2020-08-12: CVE Published. CVE-2020-17496 is published to NVD.
- 2021-11-03: CISA KEV. CVE-2020-17496 is added to the Known Exploited Vulnerabilities catalog by CISA.
- 2022-05-03: CISA Remediation Deadline. Expiration of the CISA remediation deadline as described in [BOD 22-01](https://www.cisa.gov/news-events/directives/bod-22-01-reducing-significant-risk-known-exploited-vulnerabilities).
- 2023-12-15: Rule Released. CrowdSec releases a rule to detect CVE-2020-17496 exploitation attempts against the CrowdSec Network.
- 2024-11-23: CrowdSec First Seen. CrowdSec observes in-the-wild exploitation of CVE-2020-17496 for the first time.

## References

- https://cwe.mitre.org/data/definitions/78.html
- https://blog.exploitee.rs/2020/exploiting-vbulletin-a-tale-of-patch-fail/
- https://forum.vbulletin.com/forum/vbulletin-announcements/vbulletin-announcements_aa/4445227-vbulletin-5-6-0-5-6-1-5-6-2-security-patch
- https://seclists.org/fulldisclosure/2020/Aug/5
- https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2020/CVE-2020-17496.yaml

## Live exploitation data

The [Live Exploit Tracker page](https://tracker.crowdsec.net/cves/CVE-2020-17496) follows observed exploitation activity for CVE-2020-17496. [Request an API key](https://tracker.crowdsec.net/request-api-key) for full access to its exploitation timeline, attacking IP addresses and blocklists.