How severe is CVE-2020-5216?

CVE-2020-5216 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2020-5216 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-5216?

CVE-2020-5216 affects Twitter Secure Headers. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-5216?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-5216 published?

CVE-2020-5216 was published on 2020-01-23 and last updated on 2026-06-17.

CVE-2020-5216

CVE-2020-5216 is a medium-severity vulnerability in Twitter Secure Headers with a CVSS 3.x base score of 4.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-74.

Key facts

Severity: Medium (CVSS 3.x base score 4.4)
CVSS v2: 5.0
EPSS exploit prediction: 1% (61st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-74
Affected product: Twitter Secure Headers
Published: 2020-01-23
Last modified: 2026-06-17

Description

In Secure Headers (RubyGem secure_headers), a directive injection vulnerability is present in versions before 3.9.0, 5.2.0, and 6.3.0. If user-supplied input was passed into append/override_content_security_policy_directives, a newline could be injected leading to limited header injection. Upon seeing a newline in the header, rails will silently create a new Content-Security-Policy header with the remaining value of the original string. It will continue to create new headers for each newline. This has been fixed in 6.3.0, 5.2.0, and 3.9.0.

Frequently asked questions

What is CVE-2020-5216?: In Secure Headers (RubyGem secure_headers), a directive injection vulnerability is present in versions before 3.9.0, 5.2.0, and 6.3.0. If user-supplied input was passed into append/override_content_security_policy_directives, a newline could be injected leading to limited header injection. Upon seeing a newline in the header, rails will silently create a new Content-Security-Policy header with the remaining value of the original string. It will continue to create new headers for each newline. This has been fixed in 6.3.0, 5.2.0, and 3.9.0.
How severe is CVE-2020-5216?: CVE-2020-5216 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2020-5216 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-5216?: CVE-2020-5216 affects Twitter Secure Headers. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-5216?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-5216 published?: CVE-2020-5216 was published on 2020-01-23 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:twitter:secure_headers:*:*:*:*:*:ruby:*:*

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