Unauthenticated server crash via overlong cache filename
Published Apr 28, 2021 · Updated Aug 4, 2024
Denial of service in Etherpad before 1.8.3 allows remote attackers to crash the server by requesting a specially crafted URI. The minification cache encodes the requested asset URI into a cache filename without constraining its resulting length, and the ensuing ENAMETOOLONG filesystem error escapes as an unhandled exception. Unauthenticated network access to the asset route is sufficient; exploitation shuts down the Etherpad instance without reported data disclosure or modification.
Summary
What happened
Denial of service in Etherpad before 1.8.3 allows remote attackers to crash the server by requesting a specially crafted URI. The minification cache encodes the requested asset URI into a cache filename without constraining its resulting length, and the ensuing ENAMETOOLONG filesystem error escapes as an unhandled exception. Unauthenticated network access to the asset route is sufficient; exploitation shuts down the Etherpad instance without reported data disclosure or modification.
The record
- CVE
- CVE-2020-22781
- Published
- Apr 28, 2021
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-89, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 28, 2021CVE publishedPublication date reported by the CVE source.
- Aug 4, 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.
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
- Crafted minification URI crash reproducerproof of concept · demonstrated
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Reported exploitation
- Reported Etherpad outages from crafted URI requestsreported exploitation
Technologies
Your stack
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Your stack
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