CVE-2021-4070

Public Exploit
Off-by-one Error in v2fly/v2ray-core

Description

Off-by-one Error in GitHub repository v2fly/v2ray-core prior to 4.44.0.

Category

9.1
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 3.0 •
CVSS 2.0 •
EPSS 0.21%
Third-Party Advisory github.com Third-Party Advisory huntr.dev
Affected: v2fly v2fly/v2ray-core
Published at:
Updated at:

References

Link Tags
https://huntr.dev/bounties/8da19456-4d89-41ef-9781-a41efd6a1877 exploit third party advisory patch
https://github.com/v2fly/v2ray-core/commit/c1af2bfd7aa59a4482aa7f6ec4b9208c1d350b5c third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-4070?
CVE-2021-4070 has been scored as a critical severity vulnerability.
How to fix CVE-2021-4070?
To fix CVE-2021-4070, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-4070 being actively exploited in the wild?
It is possible that CVE-2021-4070 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-4070?
CVE-2021-4070 affects v2fly v2fly/v2ray-core.
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