CVE-2021-23354

Public Exploit
Regular Expression Denial of Service (ReDoS)

Description

The package printf before 0.6.1 are vulnerable to Regular Expression Denial of Service (ReDoS) via the regex string /\%(?:\(([\w_.]+)\)|([1-9]\d*)\$)?([0 +\-\]*)(\*|\d+)?(\.)?(\*|\d+)?[hlL]?([\%bscdeEfFgGioOuxX])/g in lib/printf.js. The vulnerable regular expression has cubic worst-case time complexity.

Category

5.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.40%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: n/a printf
Published at:
Updated at:

References

Link Tags
https://snyk.io/vuln/SNYK-JS-PRINTF-1072096 broken link
https://github.com/adaltas/node-printf/pull/32 third party advisory patch
https://github.com/adaltas/node-printf/issues/31 issue tracking exploit third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-23354?
CVE-2021-23354 has been scored as a medium severity vulnerability.
How to fix CVE-2021-23354?
To fix CVE-2021-23354, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-23354 being actively exploited in the wild?
It is possible that CVE-2021-23354 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-23354?
CVE-2021-23354 affects n/a printf.
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