Application hang via quadratic RegExp flag parsing
Published Mar 30, 2023 · Updated Nov 3, 2025
Regular expression denial of service in AngularJS 1.2.21 through 1.8.3 allows remote attackers to hang applications through angular.copy(). The RegExp branch converts the object to a string and applies /[^/]*$/ to recover its flags, causing quadratic backtracking on a long pattern instead of reading the flags property. Exploitation requires an application path that passes an attacker-controlled RegExp object to angular.copy(), and the resulting CPU consumption interrupts that application.
Summary
What happened
Regular expression denial of service in AngularJS 1.2.21 through 1.8.3 allows remote attackers to hang applications through angular.copy(). The RegExp branch converts the object to a string and applies /[^/]*$/ to recover its flags, causing quadratic backtracking on a long pattern instead of reading the flags property. Exploitation requires an application path that passes an attacker-controlled RegExp object to angular.copy(), and the resulting CPU consumption interrupts that application.
The record
- CVE
- CVE-2023-26116
- Published
- Mar 30, 2023
- Updated
- Nov 3, 2025
- Vendor
- Angular
- Product
- AngularJS
- Classifications
- CWE-1333, T1499.003
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 30, 2023CVE publishedPublication date reported by the CVE source.
- Nov 3, 2025Record 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?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <*
- Affected versionversion=1.2.21 <*
- Affected versionversion=1.2.23 <*
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
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
- AngularJS angular.copy ReDoS proof of conceptproof 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