CVE-2019-12739 — lib/Controller/ExtractionController

lib/Controller/ExtractionController.php in the Extract add-on before 1.2.0 for Nextcloud allows Remote Code Execution via shell metacharacters in a RAR filename via ajax/extractRar.php (nameOfFile and directory parameters).

01What is this vulnerability?

lib/Controller/ExtractionController.php in the Extract add-on before 1.2.0 for Nextcloud allows Remote Code Execution via shell metacharacters in a RAR filename via ajax/extractRar.php (nameOfFile and directory parameters).

02Affected products

Vendor	Product	Versions
n	a / n/a	n/a

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2019-06-05T13:57:32.000Z
• Last modified: 2024-08-04T23:32:54.186Z

09References

• hackerone.com — https://hackerone.com/reports/546753
• www.secsignal.org — https://www.secsignal.org/news/a-tale-of-rce-nextcloud-extract-app/