Document-content substitution via CRC32 cache-key collisions
Published Jul 27, 2021 · Updated Aug 3, 2024
Improper authorization in Open-Xchange OX Documents before 7.10.5-rev5 allows remote authenticated users to receive another document's content. The office component uses CRC32 values as document-cache keys, so colliding XML structures cause cached content for one uploaded file to be served for another. Exploitation requires an authenticated user able to upload and edit two colliding documents; the resulting substitution exposes or alters document content.
Summary
What happened
Improper authorization in Open-Xchange OX Documents before 7.10.5-rev5 allows remote authenticated users to receive another document's content. The office component uses CRC32 values as document-cache keys, so colliding XML structures cause cached content for one uploaded file to be served for another. Exploitation requires an authenticated user able to upload and edit two colliding documents; the resulting substitution exposes or alters document content.
The record
- CVE
- CVE-2021-28095
- Published
- Jul 27, 2021
- Updated
- Aug 3, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-285, CWE-326, T1213, T1565
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 27, 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
- Open-Xchange XML collision reproduction procedureproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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