Arbitrary Code Injection in reduce-css-calc

published 2018-05-31 8 y ago modified 2026-06-17 4 mo ago also GHSA-4662-j96g-mv46 , EUVD-2018-0196

cvss: 6.1; version 3.0, NVD
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

Arbitrary code execution is possible in reduce-css-calc node module <=1.2.4 through crafted css. This makes cross sites scripting (XSS) possible on the client and arbitrary code injection possible on the server and user input is passed to the `calc` function.

Patch / fix

fixed in 1

npm reduce-css-calc 1.2.5

Exploit prediction

1.19% chance of exploitation in the next 30 days, higher than 68% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

gist.github.com https://gist.github.com/ChALkeR/415a41b561ebea9b341efbb40b802fc9 referenced PoC, tagged "exploit" by a source, unverified
nodesecurity.io https://nodesecurity.io/advisories/144 referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
NVD	3.0	6.1	CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
NVD	2.0	4.3	AV:N/AC:M/Au:N/C:N/I:P/A:N

Affected packages

ecosystem	package	affected	fixed in
npm	reduce-css-calc	<1.2.5	1.2.5

Affected products

HackerOne reduce-css-calc node module

Classification

Weakness

CWE-94 Improper Control of Generation of Code
CWE-79 Improper Neutralization of Input During Web Page Generation

References

gist.github.com /ChALkeR/415a41b561ebea9b341efbb40b802fc9
web, exploit, third-party-advisory
nodesecurity.io /advisories/144
exploit, third-party-advisory
nvd.nist.gov /vuln/detail/CVE-2016-10548
advisory
github.com /advisories/GHSA-4662-j96g-mv46
advisory
npmjs.com /advisories/144
web

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary