CVE-2021-33626
A vulnerability exists in SMM (System Management Mode) branch that registers a SWSMI handler that does not sufficiently check or validate the allocated buffer pointer(QWORD values for CommBuffer).
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.31%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
A vulnerability exists in SMM (System Management Mode) branch that registers a SWSMI handler that does not sufficiently check or validate the allocated buffer pointer(QWORD values for CommBuffer). This can be used by an attacker to corrupt data in SMRAM memory and even lead to arbitrary code execution.
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.31% probability · 23th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-829
- Affected
- insyde/insydeh2o · siemens/ruggedcom apr1808 firmware · siemens/simatic field pg m5 firmware · siemens/simatic field pg m6 firmware · siemens/simatic ipc127e firmware · siemens/simatic ipc227g firmware · siemens/simatic ipc277g firmware · siemens/simatic ipc327g firmware · siemens/simatic ipc377g firmware · siemens/simatic ipc427e firmware · siemens/simatic ipc477e firmware · siemens/simatic ipc477e pro firmware · siemens/simatic ipc627e firmware · siemens/simatic ipc647e firmware · siemens/simatic ipc677e firmware · siemens/simatic ipc847e firmware · siemens/simatic itp1000 firmware
- Source
- cve@mitre.org
EPSS 0.3% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdfThird Party Advisory
- https://security.netapp.com/advisory/ntap-20220216-0006/Third Party Advisory
- https://www.insyde.com/security-pledgeVendor Advisory
- https://www.insyde.com/security-pledge/SA-2021001Vendor Advisory
- https://cert-portal.siemens.com/productcert/pdf/ssa-306654.pdfThird Party Advisory
- https://security.netapp.com/advisory/ntap-20220216-0006/Third Party Advisory
- https://www.insyde.com/security-pledgeVendor Advisory
- https://www.insyde.com/security-pledge/SA-2021001Vendor Advisory
- https://www.kb.cert.org/vuls/id/796611
- https://cert-portal.siemens.com/productcert/html/ssa-306654.html
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.