CVE-2019-10842

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 v3.0 NVD

9.8 CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS v2.0 NVD

10.0 HIGHAV:N/AC:L/Au:N/C:C/I:C/A:C

EPSS

4.92% chance of exploitation in the next 30 days, 92nd percentile

Published

2019-04-04

Updated

2024-08-04

Proof-of-concept exploits (1)

• https://snyk.io/vuln/SNYK-RUBY-BOOTSTRAPSASS-174093

Security advisories

• http://dgb.github.io/2019/04/05/bootstrap-sass-backdoor.html
• twbs/bootstrap-sass/issues/1195
• https://snyk.io/blog/malicious-remote-code-execution-backdoor-discovered-in-the-popular-b…
• advisories/GHSA-vqqv-v9m2-48p2

References

• CVE Record
• NVD entry