secure_headers manages application of security headers with many safe defaults. Prior to 7.3.0, secure_headers builds the Content-Security-Policy value by stitching directives with ; separators, and build_sandbox_list_directive, build_media_type_list_directive, and build_report_to_directive interpolate caller-supplied strings without scrubbing ;, \r, or \n. When untrusted input reaches SecureHeaders.override_content_security_policy_directives or append APIs for :sandbox, :plugin_types, or :report_to, an attacker can inject a CSP directive such as script-src 'unsafe-inline' * before the legitimate script-src, enabling XSS reachability through these sinks or CSP report exfiltration. This issue is fixed in version 7.3.0.
CVE-2026-54163
MEDIUMPre-NVD 4.74.7—Elevated
EchelonGraph scoreMEDIUM confidence
This medium-severity CVE scores 4.7 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3%, top 79% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
Triggered by: NVD CVSS baseline
Sources: epss, secondary
4.7
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
- Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 4.7Exploit: NoneExposed: 0
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 4.7
- EG Score
- 4.7(medium)
- EPSS
- 20.7%
- KEV
- Not listed
Published
July 10, 2026
Last Modified
July 20, 2026
Advisory Details (3)
Auto-updated Jul 17, 2026🔬 Proof of concept available. Patch available. Sources: github_release, github, github_commit.
github Patch Available🟡 PoC Available
CSP directive injection via sandbox, plugin_types, and report_to when given untrusted input · Advisory · github/secure_headers · GitHub
https://github.com/github/secure_headers/security/advisories/GHSA-rqq5-2gf9-4w4qgithub_release Patch Available
v7.3.0
Patch available: github/secure_headers v7.3.0
https://github.com/github/secure_headers/releases/tag/v7.3.0github_commit Patch Available
commit 286a79dea80c (github/secure_headers)
Patch available: github/secure_headers v7.3.0 (contains commit 286a79dea80c)
https://github.com/github/secure_headers/commit/286a79dea80c6a9be4ca93e0f284c923cf77e539Vendor Advisories for CVE-2026-54163(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Affected Packages
(1 across 1 ecosystem)
RubyGems(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| secure_headers | 0.1.0 ... 7.2.0 (113 versions) | 7.3.0 | — |
Weakness Classification(2)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 7× in last 7d / 8× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-22 14:08 UTCEPSS rescore
- 2026-07-21 15:25 UTCEPSS rescore
- 2026-07-20 17:08 UTCEPSS rescore
- 2026-07-19 14:31 UTCEPSS rescore
- 2026-07-19 14:31 UTCEPSS rescore
- 2026-07-19 03:42 UTCEG score recompute
- 2026-07-19 02:29 UTCEPSS rescore
- 2026-07-10 21:12 UTCEG score recompute
Related CVEs(same CWE)
Frequently asked(5)
What is CVE-2026-54163?
CVE-2026-54163 is a medium vulnerability published on July 10, 2026. secureheaders manages application of security headers with many safe defaults. Prior to 7.3.0, secureheaders builds the Content-Security-Policy value by stitching directives with ; separators, and buildsandboxlistdirective, buildmediatypelistdirective, and buildreporttodirective interpolate…
When was CVE-2026-54163 disclosed?
CVE-2026-54163 was first published in the National Vulnerability Database on July 10, 2026, with the most recent update on July 20, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-54163 actively exploited?
CVE-2026-54163 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 20.7% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-54163?
CVE-2026-54163 has a CVSS v3 base score of 4.7 (NVD).
How do I remediate CVE-2026-54163?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-54163, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.
Dependency Blast Radius
See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-54163
Is Your Infrastructure Affected by CVE-2026-54163?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.