Sensitive information disclosure via integer overflow
Published Mar 10, 2021 · Updated Jul 9, 2026
Integer overflow in the Nginx webserver of ExpressVPN Router version 1 allows remote attackers to obtain sensitive information via crafted requests. The Nginx range filter module mishandles integer calculations while processing a specially crafted request, causing memory contents to be exposed. Exploitation requires access to the router control panel, typically restricted to the local network; the documented impact is information disclosure without reported integrity or availability effects.
Summary
What happened
Integer overflow in the Nginx webserver of ExpressVPN Router version 1 allows remote attackers to obtain sensitive information via crafted requests. The Nginx range filter module mishandles integer calculations while processing a specially crafted request, causing memory contents to be exposed. Exploitation requires access to the router control panel, typically restricted to the local network; the documented impact is information disclosure without reported integrity or availability effects.
The record
- CVE
- CVE-2020-29238
- Published
- Mar 10, 2021
- Updated
- Jul 9, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-190, T1210
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 10, 2021CVE publishedPublication date reported by the CVE source.
- Jul 9, 2026Record 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.
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
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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