CVE-2018-5721 json
Stack-based buffer overflow in the ej_update_variables function in router/httpd/web.c on ASUS routers (when using software from https://git…
published 2018-01-17 8 y ago modified 2026-06-17 4 mo ago also EUVD-2018-17490
- cvss
- 8.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.9%
- EPSS 1.9% chance of exploitation in 30 days, percentile 80%
- public exploits
- 0
- none known
Summary
Stack-based buffer overflow in the ej_update_variables function in router/httpd/web.c on ASUS routers (when using software from https://github.com/RMerl/asuswrt-merlin) allows web authenticated attackers to execute code via a request that updates a setting. In ej_update_variables, the length of the variable action_script is not checked, as long as it includes a "_wan_if" substring.
Exploit prediction
1.94% chance of exploitation in the next 30 days, higher than 80% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- w0lfzhang.com http://www.w0lfzhang.com/2018/01/17/ASUS-router-stack-overflow-in-http-server/ referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 6.5 | AV:N/AC:L/Au:S/C:P/I:P/A:P |
Classification
- Weakness
-
- CWE-787 Out-of-bounds Write
References
-
w0lfzhang.com
/2018/01/17/ASUS-router-stack-overflow-in-http-server/
exploit, third-party-advisory
Sources
- CVE List CVE-2018-5721
- NVD CVE-2018-5721
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