Parsing stall via unvalidated DOCTYPE entity regex
Published Jun 6, 2023 · Updated Aug 2, 2024
Regular-expression denial of service in Natural Intelligence fast-xml-parser 4.1.3 through 4.2.3 allows remote attackers to stall XML parsing. DocTypeReader accepts special characters in an entity name and interpolates the name into a RegExp used to search and replace entities, enabling attacker-controlled catastrophic matching. The flaw is reachable when an application parses attacker-controlled XML with DOCTYPE entity processing enabled, and exploitation can leave the parser stalled indefinitely.
Summary
What happened
Regular-expression denial of service in Natural Intelligence fast-xml-parser 4.1.3 through 4.2.3 allows remote attackers to stall XML parsing. DocTypeReader accepts special characters in an entity name and interpolates the name into a RegExp used to search and replace entities, enabling attacker-controlled catastrophic matching. The flaw is reachable when an application parses attacker-controlled XML with DOCTYPE entity processing enabled, and exploitation can leave the parser stalled indefinitely.
The record
- CVE
- CVE-2023-34104
- Published
- Jun 6, 2023
- Updated
- Aug 2, 2024
- Vendor
- Natural Intelligence
- Product
- fast-xml-parser
- Classifications
- CWE-400, CWE-1333, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 6, 2023CVE publishedPublication date reported by the CVE source.
- Aug 2, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=>= 4.1.3, < 4.2.4
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What is affected?
Published CVSS scores
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Attacks
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Technologies
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Your stack
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