Service interruption via inefficient email validation
Published Jun 27, 2022 · Updated Aug 4, 2024
Regular expression denial of service in scniro-validator 1.0.1 allows remote attackers to interrupt service via crafted invalid email input. The validate function applies the email regular expression to a long domain-like string and delays rejection until its terminal exclamation mark, causing disproportionate evaluation time. Exposure requires an application to pass unbounded attacker-controlled email values into the library, where CPU consumption stalls Node.js event-loop work.
Summary
What happened
Regular expression denial of service in scniro-validator 1.0.1 allows remote attackers to interrupt service via crafted invalid email input. The validate function applies the email regular expression to a long domain-like string and delays rejection until its terminal exclamation mark, causing disproportionate evaluation time. Exposure requires an application to pass unbounded attacker-controlled email values into the library, where CPU consumption stalls Node.js event-loop work.
The record
- CVE
- CVE-2021-40901
- Published
- Jun 27, 2022
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-1333, T1499
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 27, 2022CVE publishedPublication date reported by the CVE source.
- Aug 4, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- scniro-validator ReDoS timing proofproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo