Authenticated code execution via unchecked CSR fields
Published Dec 22, 2021 · Updated Aug 3, 2024
Stack-based buffer overflow in Lantronix PremierWave 2050 8.9.0.0R4 allows remote authenticated users to execute code via HTTP. The ltrx_evo handler for the SslGenerateCSR AJAX directive appends the s, l, o, ou, and cn POST fields to a 1,048-byte stack buffer with unvalidated strcat calls. An account with the ssl permission is required; an oversized field corrupts the stack frame and gives control of the program counter, enabling code execution on the device.
Summary
What happened
Stack-based buffer overflow in Lantronix PremierWave 2050 8.9.0.0R4 allows remote authenticated users to execute code via HTTP. The ltrx_evo handler for the SslGenerateCSR AJAX directive appends the s, l, o, ou, and cn POST fields to a 1,048-byte stack buffer with unvalidated strcat calls. An account with the ssl permission is required; an oversized field corrupts the stack frame and gives control of the program counter, enabling code execution on the device.
The record
- CVE
- CVE-2021-21887
- Published
- Dec 22, 2021
- Updated
- Aug 3, 2024
- Vendor
- Lantronix
- Product
- PremierWave 2050
- Classifications
- CWE-121, CWE-787, T1190
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Dec 22, 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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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=Lantronix PremierWave 2050 8.9.0.0R4 (in QEMU)
What conditions does exploitation require?
What is affected?
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
- Cisco Talos SslGenerateCSR HTTP proof of conceptproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
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Your stack
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