CVE-2020-26256

Public Exploit
Denial of service in fast-csv

Description

Fast-csv is an npm package for parsing and formatting CSVs or any other delimited value file in node. In fast-cvs before version 4.3.6 there is a possible ReDoS vulnerability (Regular Expression Denial of Service) when using ignoreEmpty option when parsing. This has been patched in `v4.3.6` You will only be affected by this if you use the `ignoreEmpty` parsing option. If you do use this option it is recommended that you upgrade to the latest version `v4.3.6` This vulnerability was found using a CodeQL query which identified `EMPTY_ROW_REGEXP` regular expression as vulnerable.

Category

5.7
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.07% Top 25%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory lgtm.com Third-Party Advisory npmjs.com
Affected: C2FO fast-csv
Published at:
Updated at:

References

Link Tags
https://github.com/C2FO/fast-csv/security/advisories/GHSA-8cv5-p934-3hwp third party advisory
https://lgtm.com/query/8609731774537641779/ third party advisory exploit
https://github.com/C2FO/fast-csv/issues/540 third party advisory
https://github.com/C2FO/fast-csv/commit/4bbd39f26a8cd7382151ab4f5fb102234b2f829e third party advisory patch
https://www.npmjs.com/package/%40fast-csv/parse
https://www.npmjs.com/package/fast-csv third party advisory product

Frequently Asked Questions

What is the severity of CVE-2020-26256?
CVE-2020-26256 has been scored as a medium severity vulnerability.
How to fix CVE-2020-26256?
To fix CVE-2020-26256, 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-2020-26256 being actively exploited in the wild?
It is possible that CVE-2020-26256 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-26256?
CVE-2020-26256 affects C2FO fast-csv.
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