What is CVE-2026-54163?

CVE-2026-54163 is a medium-severity vulnerability in Github Secure_headers, classified under Cross-site Scripting. CVSS score: 4.7/10. Published 2026-07-17.

How severe is CVE-2026-54163?

Medium severity. CVSS v3 base score is 4.7 out of 10.

XSS in Github Secure_headers

CVE-2026-54163

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_medi…

Vulnerability class: XSS (Cross-Site Scripting)

CVSS v3 metric

CVSS v3 base score 4.7 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N.

Affected products

Github Secure_headers — versions < 7.3.0

Weakness classification (CWE)

CWE-79 — Cross-site Scripting
CWE-113 — HTTP Response Splitting

References

security-advisories@github.com (x_refsource_CONFIRM)
security-advisories@github.com (x_refsource_MISC)
security-advisories@github.com (x_refsource_MISC)

Frequently asked questions

What is CVE-2026-54163?: CVE-2026-54163 is a medium-severity vulnerability in Github Secure_headers, classified under Cross-site Scripting. CVSS score: 4.7/10. Published 2026-07-17.
How severe is CVE-2026-54163?: Medium severity. CVSS v3 base score is 4.7 out of 10.