Authenticated command injection via fax extension
Published Nov 5, 2021 · Updated Aug 4, 2024
Improper input validation in FusionPBX before 4.5.30 allows remote authenticated users to execute commands via crafted fax_extension values. The app/fax/fax_send.php handler accepts any nonempty fax_extension and incorporates it into fax directory paths that are created through FreeSWITCH event-socket commands, so shell metacharacters can alter command execution. Authentication to the FusionPBX interface is required, and successful exploitation can provide remote code execution with the service account's privileges.
Summary
What happened
Improper input validation in FusionPBX before 4.5.30 allows remote authenticated users to execute commands via crafted fax_extension values. The app/fax/fax_send.php handler accepts any nonempty fax_extension and incorporates it into fax directory paths that are created through FreeSWITCH event-socket commands, so shell metacharacters can alter command execution. Authentication to the FusionPBX interface is required, and successful exploitation can provide remote code execution with the service account's privileges.
The record
- CVE
- CVE-2021-43405
- Published
- Nov 5, 2021
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- T1190
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Nov 5, 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 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
- FusionPBX 4.5.29 Remote Code Executionproof of concept · unverified
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Technologies
Your stack
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Your stack
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