Code execution via namespace-separator injection
Published Feb 16, 2022 · Updated May 5, 2025
Improper input validation in Expat before 2.4.5 allows attackers to execute code through crafted XML namespace declarations. The addBinding path in xmlparse.c accepts an xmlns URI containing the parser's namespace separator, creating an ambiguous expanded name for downstream XML processors. Exploitation requires attacker-controlled XML, namespace processing, and a consuming processor that mishandles the malformed name; demonstrated outcomes include code execution.
Summary
What happened
Improper input validation in Expat before 2.4.5 allows attackers to execute code through crafted XML namespace declarations. The addBinding path in xmlparse.c accepts an xmlns URI containing the parser's namespace separator, creating an ambiguous expanded name for downstream XML processors. Exploitation requires attacker-controlled XML, namespace processing, and a consuming processor that mishandles the malformed name; demonstrated outcomes include code execution.
The record
- CVE
- CVE-2022-25236
- Published
- Feb 16, 2022
- Updated
- May 5, 2025
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-668, T1203
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Feb 16, 2022CVE publishedPublication date reported by the CVE source.
- May 5, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
Affected products and versions are unavailable in this record.
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
- Zoom XMPP Stanza Smuggling remote code execution chainfunctional · demonstrated
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Technologies
Your stack
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Your stack
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