Service interruption via quadratic port-regex backtracking
Published Jun 29, 2023 · Updated Nov 4, 2025
ReDoS in Ruby uri gem 0.12.1 and earlier allows remote attackers to interrupt services by submitting crafted invalid URLs. PORT validation in rfc3986_parser.rb applies a backtracking-prone regular expression to leading whitespace in an invalid port number, causing quadratic parse time; the related rfc2396 parser also mishandles invalid URLs. Exposure requires an application to pass attacker-controlled URL text to an affected URI parser, and repeated or long inputs consume CPU and delay or interrupt that application's service.
Summary
What happened
ReDoS in Ruby uri gem 0.12.1 and earlier allows remote attackers to interrupt services by submitting crafted invalid URLs. PORT validation in rfc3986_parser.rb applies a backtracking-prone regular expression to leading whitespace in an invalid port number, causing quadratic parse time; the related rfc2396 parser also mishandles invalid URLs. Exposure requires an application to pass attacker-controlled URL text to an affected URI parser, and repeated or long inputs consume CPU and delay or interrupt that application's service.
The record
- CVE
- CVE-2023-36617
- Published
- Jun 29, 2023
- Updated
- Nov 4, 2025
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-1333, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 29, 2023CVE publishedPublication date reported by the CVE source.
- Nov 4, 2025Record updatedLatest update available in the CVE record.
Exploitability
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What is affected?
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Published CVSS scores
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Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
- Invalid-port quadratic-backtracking regression testproof of concept · demonstrated
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Technologies
Your stack
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