An issue was discovered in iscflashx64.sys 3.9.3.0 in Insyde H2OFFT 6.20.00.
Priority LOW 32CWE-787Published · Updated
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- High · None · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA.
Summary
An issue was discovered in iscflashx64.sys 3.9.3.0 in Insyde H2OFFT 6.20.00. When handling IOCTL 0x22229a, the input used to allocate a buffer and copy memory is mishandled. This could cause memory corruption or a system crash.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00189 8th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | — | all versions | — | No fix listed | CNA |
- — Vendor— Affected all versions Fixed in — No fix listed CNA
CPE configurations NVD · 2
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:insyde:h2offt:6.20.00:*:*:*:*:*:*:* | 6.20.00 | Vulnerable | Insyde Software |
| cpe:2.3:a:insyde:iscflashx64.sys:3.9.3.0:*:*:*:*:*:*:* | 3.9.3.0 | Vulnerable | Insyde Software |
- cpe:2.3:a:insyde:h2offt:6.20.00:*:*:*:*:*:*:* Versions 6.20.00 Vulnerable ·Insyde Software
- cpe:2.3:a:insyde:iscflashx64.sys:3.9.3.0:*:*:*:*:*:*:* Versions 3.9.3.0 Vulnerable ·Insyde Software
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2021-33834
- 2026-10-03 Alias added: GHSA-2q86-2ww4-wc89
References
More Insyde Software H2offt vulnerabilities
- TI-2019-09362 Improper access control in the Insyde software tools may allow an authenticated user to… CVSS 3.1HIGH 7.8
Sources
- CVE-2021-33834 · CVE Program
- CVE-2021-33834 · NVD
- FIRST EPSS
- GHSA-2q86-2ww4-wc89 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences