CVE-2021-26109
Last modified
CVE-2021-26109 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. 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.. EPSS estimates a 1.82% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Fortinet | Fortios | >= 6.0.0, <= 6.0.12 |
| Fortinet | Fortios | >= 6.2.0, <= 6.2.9 |
| Fortinet | Fortios | >= 6.4.0, <= 6.4.5 |
| Fortinet | Fortios | 7.0.0 |
References
- https://fortiguard.com/advisory/FG-IR-21-049Patch, Vendor Advisory
- https://fortiguard.com/advisory/FG-IR-21-049Patch, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Modified
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How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
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