CVE-2019-10842
highpriority · track · 41EPSS 0.049 · 92 %ileEUUSEPSS · scored 2026-10-28
Arbitrary code execution (via backdoor code) was discovered in bootstrap-sass 3.2.0.3, when downloaded from rubygems.org. An unauthenticated attacker can craft the ___cfduid cookie value with base64 arbitrary code to be executed via eval(), which can be leveraged to execute arbitrary code on the target system. Note that there are three underscore characters in the cookie name. This is unrelated to the __cfduid cookie that is legitimately used by Cloudflare.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 9–10
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (3)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- GHSA-vqqv-v9m2-48p2Bootstrap-sass contains code execution backdoor2019-04-04ghsa · osvUS
Arbitrary code execution (via backdoor code) was discovered in bootstrap-sass 3.2.0.3, when downloaded from rubygems.org. An unauthenticated attacker can craft the ___cfduid cookie value with base64 arbitrary code to be executed via eval(), which can be leveraged to execute arbitrary code on the target system. Note that there are three underscore characters in the cookie name. This is unrelated to the __cfduid cookie that is legitimately used by Cloudflare.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (14)
External citations — patches, advisories, analysis.
- http://dgb.github.io/2019/04/05/bootstrap-sass-backdoor.htmlcnnvd
- https://github.com/twbs/bootstrap-sass/commit/989f4e8f146da7f19362bbd85dc4c8e26b2bd43ePatchcnnvd
- https://github.com/twbs/bootstrap-sass/issues/1195cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2019-10842cnnvd
- https://snyk.io/blog/malicious-remote-code-execution-backdoor-discovered-in-the-popular-bootstrap-sass-ruby-gem/cnnvd
- https://snyk.io/vuln/SNYK-RUBY-BOOTSTRAPSASS-174093cnnvd
- http://dgb.github.io/2019/04/05/bootstrap-sass-backdoor.htmlenisa_euvd
- https://github.com/twbs/bootstrap-sass/issues/1195enisa_euvd
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