Unauthenticated PHP execution via colon filename bypass
Published Apr 7, 2022 · Updated Aug 4, 2024
Unrestricted file upload in Studio-42 elFinder 2.0.4 through 2.1.59 allows remote attackers to execute PHP code via crafted filenames. The LocalFileSystem volume accepts a name such as webshell.php:aaa on Windows, where the colon bypasses extension validation while the filesystem creates an executable PHP file. An exposed connector.minimal.php endpoint requires no privileges or user interaction, and exploitation runs attacker-supplied PHP in the web server context.
Summary
What happened
Unrestricted file upload in Studio-42 elFinder 2.0.4 through 2.1.59 allows remote attackers to execute PHP code via crafted filenames. The LocalFileSystem volume accepts a name such as webshell.php:aaa on Windows, where the colon bypasses extension validation while the filesystem creates an executable PHP file. An exposed connector.minimal.php endpoint requires no privileges or user interaction, and exploitation runs attacker-supplied PHP in the web server context.
The record
- CVE
- CVE-2021-43421
- Published
- Apr 7, 2022
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-434, T1190, T1505.003
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 7, 2022CVE 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.
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
- Colon filename bypass proof of conceptproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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