CVE-2021-26109

Description

An integer overflow or wraparound vulnerability in the memory allocator of SSLVPN in FortiOS before 7.0.1 may allow an unauthenticated attacker to corrupt control data on the heap via specifically crafted requests to SSLVPN, resulting in potentially arbitrary code execution.

Category

8.1
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.34% Top 25%
Vendor Advisory fortiguard.com
Affected: Fortinet Fortinet FortiOS
Published at:
Updated at:

References

Link Tags
https://fortiguard.com/advisory/FG-IR-21-049 patch vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-26109?
CVE-2021-26109 has been scored as a high severity vulnerability.
How to fix CVE-2021-26109?
To fix CVE-2021-26109, 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-2021-26109 being actively exploited in the wild?
It is possible that CVE-2021-26109 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-26109?
CVE-2021-26109 affects Fortinet Fortinet FortiOS.
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