Authenticated remote command execution via caupload overflow
Published Oct 6, 2022 · Updated Aug 4, 2024
A stack-based buffer overflow in ASUS RT-AX56U firmware 3.0.0.4.386.44266 allows remote authenticated users to execute commands through the HTTP service. The caupload input handler passes attacker-controlled data to strcat without limiting the 0xFFFF-byte input, overwriting stack memory. Authentication to the router management service is required, and successful exploitation can compromise confidentiality, integrity, and availability through command execution.
Summary
What happened
A stack-based buffer overflow in ASUS RT-AX56U firmware 3.0.0.4.386.44266 allows remote authenticated users to execute commands through the HTTP service. The caupload input handler passes attacker-controlled data to strcat without limiting the 0xFFFF-byte input, overwriting stack memory. Authentication to the router management service is required, and successful exploitation can compromise confidentiality, integrity, and availability through command execution.
The record
- CVE
- CVE-2021-40556
- Published
- Oct 6, 2022
- Updated
- Aug 4, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-787, T1190
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Oct 6, 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
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
Your stack
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Your stack
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