CVE-2021-26109 json
An integer overflow or wraparound vulnerability in the memory allocator of SSLVPN in FortiOS before 7.0.1 may allow an unauthenticated atta…
published 4y ago modified 4mo ago also EUVD-2021-12930
- cvss
- 8.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.9%
- EPSS 1.9% chance of exploitation in 30 days, percentile 79%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- fortiguard.com/advisory/FG-IR-21-049 advisory
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- Exploitation
- none
- Automatable
- no
- Technical impact
- total
- Assessed
- 2y ago
Exploit prediction
1.88% chance of exploitation in the next 30 days, higher than 79% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:P/RL:U/RC:C |
| CNA | 3.1 | 8.1 | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.5 | AV:N/AC:L/Au:N/C:P/I:P/A:P |
Affected products
- Fortinet Fortinet FortiOS
Classification
- Weakness
-
- CWE-190 Integer Overflow or Wraparound
- Technology feeds
References
-
fortiguard.com
/advisory/FG-IR-21-049
patch, vendor-advisory
Sources
- CVE List CVE-2021-26109
- NVD CVE-2021-26109
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