Application hang via nested foreign-content templates
Published May 26, 2021 · Updated Aug 3, 2024
Infinite-loop denial of service in golang.org/x/net/html before 0.0.0-20210520170846-37e1c6afe023 allows attackers to hang applications. The HTML parser repeatedly processes template elements nested within MathML or SVG foreign content instead of reaching an exit condition. Exploitation requires an application to pass attacker-controlled HTML to an affected parsing function; the nonreturning parse consumes execution capacity and interrupts service.
Summary
What happened
Infinite-loop denial of service in golang.org/x/net/html before 0.0.0-20210520170846-37e1c6afe023 allows attackers to hang applications. The HTML parser repeatedly processes template elements nested within MathML or SVG foreign content instead of reaching an exit condition. Exploitation requires an application to pass attacker-controlled HTML to an affected parsing function; the nonreturning parse consumes execution capacity and interrupts service.
The record
- CVE
- CVE-2021-33194
- Published
- May 26, 2021
- Updated
- Aug 3, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-835, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- May 26, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What conditions does exploitation require?
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
- Upstream foreign-content template regression inputsproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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