GHSA-9c24-g32g-35rj · Severity: critical · Ecosystem: composer — Drupal PECL YAML parser unsafe object handling
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.
Conclusion & alert: CVE-2017-6920 is rated High Risk (72.8/100): CVSS Critical severity, with high exploitation likelihood (EPSS 66.15%, 98th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. Mandatory action: High exploitation likelihood—assess exposure and prioritize remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-02-20 | 67.04% | 66.15% | -0.89% |
| 2 | 2025-07-30 | 67.68% | 67.04% | -0.64% |
| 3 | 2025-05-22 | — | 67.68% | — |
Full EPSS history (16 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 9.8 | 3.0 | CRITICAL |
|
3.9 | 5.9 | [email protected] |
| 7.5 | 2.0 | HIGH |
|
10.0 | 6.4 | [email protected] |
GHSA-9c24-g32g-35rj · Severity: critical · Ecosystem: composer — Drupal PECL YAML parser unsafe object handling
| URL | Tags |
|---|---|
| http://www.securityfocus.com/bid/99211 | Third Party Advisory VDB Entry |
| http://www.securitytracker.com/id/1038781 | Third Party Advisory VDB Entry |
| https://www.drupal.org/forum/newsletters/security-advisories-for-drupal-core/2017-06-21/drupal-core-multiple | Patch Vendor Advisory |