CVE-2022-35408 — An issue was discovered in Insyde InsydeH2O with kernel 5

An issue was discovered in Insyde InsydeH2O with kernel 5.0 through 5.5. An SMM callout vulnerability in the SMM driver in UsbLegacyControlSmm leads to possible arbitrary code execution in SMM and escalation of privileges. An attacker could overwrite the function pointers in the

01What is this vulnerability?

An issue was discovered in Insyde InsydeH2O with kernel 5.0 through 5.5. An SMM callout vulnerability in the SMM driver in UsbLegacyControlSmm leads to possible arbitrary code execution in SMM and escalation of privileges. An attacker could overwrite the function pointers in the EFI_BOOT_SERVICES table before the USB SMI handler triggers. (This is not exploitable from code running in the…

02Affected products

Vendor	Product	Versions
n	a / n/a	n/a

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2022-09-22T15:35:26.000Z
• Last modified: 2025-05-27T15:50:35.592Z

09References

• www.insyde.com — https://www.insyde.com/security-pledge
• www.insyde.com — https://www.insyde.com/security-pledge/SA-2022031
• binarly.io — https://binarly.io/advisories/BRLY-2022-022/index.html