CVE-2017-6920
Drupal core 8 before versions 8.3.4 allows remote attackers to execute arbitrary code due to the PECL YAML parser not handling PHP objects safely during certain operations.
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 20.2%, higher than 97% of all known CVEs. Patch or mitigate before the next change window.
Description
Drupal core 8 before versions 8.3.4 allows remote attackers to execute arbitrary code due to the PECL YAML parser not handling PHP objects safely during certain operations.
- CVSS 3.0
- 9.8 CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 20.24% probability · 97th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-19
- Affected
- drupal/drupal
- Source
- mlhess@drupal.org
EPSS moved from 15.6% on 21 September 2026 to 20.2% on 27 October 2026, peaking at 20.5% on 22 September 2026. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”.
References
- http://www.securityfocus.com/bid/99211Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1038781Third Party Advisory, VDB Entry
- https://www.drupal.org/forum/newsletters/security-advisories-for-drupal-core/2017-06-21/drupal-core-multiplePatch, Vendor Advisory
- http://www.securityfocus.com/bid/99211Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1038781Third Party Advisory, VDB Entry
- https://www.drupal.org/forum/newsletters/security-advisories-for-drupal-core/2017-06-21/drupal-core-multiplePatch, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.