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Fencer Intel
medium 4.4

CVE-2020-5216 json

Limited header injection when using dynamic overrides with user input in RubyGems secure_headers

published 6y ago modified 4mo ago also GHSA-w978-rmpf-qmwg , EUVD-2020-0281

cvss
4.4
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
1.2%
EPSS 1.2% chance of exploitation in 30 days, percentile 68%
public exploits
0
none known

Summary

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.

Patch / fix

  • rubygems secure_headers 3.9.0, 5.2.0, 6.3.0
  • twitter secure_headers 3.9.0, 5.2.0, 6.3.0
  • tfm satellite capsule 6.8, satellite 6.8 6.1-1.el7sat
  • kobo satellite capsule 6.8, satellite 6.8 0.5.1-1.el7sat
  • pulp satellite capsule 6.8, satellite 6.8 2.21.3-1.el7sat
  • gofer satellite capsule 6.8, satellite 6.8 2.12.5-7.el7sat
  • future satellite capsule 6.8, satellite 6.8 0.16.0-11.el7sat
  • ostree satellite capsule 6.8, satellite 6.8 2017.1-2.atomic.el7
  • foreman satellite capsule 6.8, satellite 6.8 2.1.2.19-1.el7sat
  • katello satellite capsule 6.8, satellite 6.8 3.16.0-1.el7sat

red hat advisories RHSA-2020:4366

Is CVE-2020-5216 in your dependencies? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

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Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2020-5216 updated cvss 5.8

rubygem-secure_headers: limited header injection when using dynamic overrides with user input

  • Red Hat CloudForms Management Engine 5 cfme-gemset
    affected: no fix planned “Will not fix”
  • Red Hat Satellite 6.8 tfm 6.1-1.el7sat, kobo 0.5.1-1.el7sat, pulp 2.21.3-1.el7sat, gofer 2.12.5-7.el7sat, receptor 0.6.3-1.el7ar, future 0.16.0-11.el7sat, +492 more Red Hat Satellite Capsule 6.8 tfm 6.1-1.el7sat, kobo 0.5.1-1.el7sat, pulp 2.21.3-1.el7sat, gofer 2.12.5-7.el7sat, future 0.16.0-11.el7sat, katello 3.16.0-1.el7sat, +246 more
    fixed: vendor fix RHSA-2020:4366

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

1.21% chance of exploitation in the next 30 days, higher than 68% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/twitter/secure_headers/security/advisories/GHSA-w978-rmpf-qmwg referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 3.1 4.4 CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N
NVD 3.1 5.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N
NVD 2.0 5.0 AV:N/AC:L/Au:N/C:N/I:P/A:N
GitHub 3.1 4.4 CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:N

Affected packages

ecosystem package affected fixed in
rubygems secure_headers
>=6.0.0, <6.3.0
>=5.0.0, <5.2.0
<3.9.0
6.3.0
5.2.0
3.9.0

Affected products

  • Twitter secure_headers

Classification

Weakness
  • CWE-113 Improper Neutralization of CRLF Sequences in HTTP Headers
  • CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component

References

Sources

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