CVE-2021-23354
CVSS v3
7.5
HIGH
EPSS Score
2.2 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
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.
Technical details
- Published
- 2021-03-12
Frequently asked questions
What is CVE-2021-23354?
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.
Is CVE-2021-23354 actively exploited?
Active exploitation of CVE-2021-23354 has not been confirmed. Its EPSS score was 2.2% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-23354?
CVE-2021-23354 has a CVSS v3 base score of 7.5 (HIGH severity).
Is CVE-2021-23354 affecting your environment?
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