CVE-2019-10842

Exp

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.

Published: 2019-04-04 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2019-10842 is rated High Exploit Risk (82.1/100): CVSS Critical severity, with high exploitation likelihood (EPSS 4.92%, 91th percentile). 2 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2019-10842

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2019-10842

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 8.90% 4.92% -3.98%
2 2026-03-05 9.21% 8.90% -0.31%
3 2026-01-18 — 9.21% —

Full EPSS history (25 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2019-10842

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.0 CRITICAL
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 5.9 [email protected]
10.0 2.0 HIGH
AV:N/AC:L/Au:N/C:C/I:C/A:C Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:C)
Complete integrity impact.
Availability impact (A:C)
Complete availability impact.
 10.0 10.0 [email protected]

Weakness enumeration for CVE-2019-10842

GitHub Security Advisory for CVE-2019-10842

GHSA-vqqv-v9m2-48p2 · Severity: critical · Ecosystem: rubygems — Bootstrap-sass contains code execution backdoor

OS Trackers for CVE-2019-10842

vendor priority summary link
redhat high — https://access.redhat.com/security/cve/CVE-2019-10842
suse critical CVE-2019-10842 severity critical: SUSE including 2 source package names (ruby2.1-rubygem-bootstrap-sass, rubygem-bootstrap-sass), 2 product×package rows across 1 product lines (SUSE Enterprise Storage 4): Known Not Affected 2. https://www.suse.com/security/cve/CVE-2019-10842/
ubuntu medium CVE-2019-10842 medium priority: Ubuntu including 3 source packages (compass-bootstrap-sass-plugin, node-bootstrap-sass, ruby-bootstrap-sass), 15 status rows across 5 suites (bionic, cosmic, trusty, upstream, xenial): DNE 7, not-affected 5, needs-triage 3. https://ubuntu.com/security/CVE-2019-10842

Affected software / configurations for CVE-2019-10842

Vendor Product Version Raw CPE
getbootstrap bootstrap-sass 3.2.0.3 cpe:2.3:a:getbootstrap:bootstrap-sass:3.2.0.3:*:*:*:*:ruby:*:*

References for CVE-2019-10842

cvelogic Threat Intelligence