Root command execution via Start_EPI stack overflow
Published Jan 9, 2023 · Updated Apr 9, 2025
Stack-based buffer overflow in Linksys WRT54GL firmware 4.30.18.006 and earlier allows remote authenticated users to execute commands as root. The httpd Start_EPI function copies attacker-controlled POST data sent to /apply.cgi without enforcing the destination stack buffer's bounds. Administrator access to the web management interface is required, and successful exploitation grants root control of the router.
Summary
What happened
Stack-based buffer overflow in Linksys WRT54GL firmware 4.30.18.006 and earlier allows remote authenticated users to execute commands as root. The httpd Start_EPI function copies attacker-controlled POST data sent to /apply.cgi without enforcing the destination stack buffer's bounds. Administrator access to the web management interface is required, and successful exploitation grants root control of the router.
The record
- CVE
- CVE-2022-43970
- Published
- Jan 9, 2023
- Updated
- Apr 9, 2025
- Vendor
- Linksys
- Product
- WRT54GL Wireless-G Broadband Router
- Classifications
- CWE-120, CWE-787, T1068
- Attack vector
- network
- Privileges
- admin
Timeline
How it unfolded
- Jan 9, 2023CVE publishedPublication date reported by the CVE source.
- Apr 9, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=Firmware <=4.30.18.006
What conditions does exploitation require?
What is affected?
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
- Vuln Research 101 Part 3 Hacking the Linksys WRT54GL via buffer overflowproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo