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TI-2021-03738 Aliases CVE-2021-20487GHSA-gwjp-78rh-pcgc

Improper signature verification in IBM Power 9 Systems

Priority MEDIUM 40CWE-347Published · Updated

Key facts

Attack vector
Network
Privileges required
High
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-347.

Summary

IBM Power9 Self Boot Engine(SBE) could allow a privileged user to inject malicious code and compromise the integrity of the host firmware bypassing the host firmware signature verification process.

Why it matters now

EPSS 0.0068 52nd percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
IBMPower 9 SystemsFW930; FW940; FW941; OP940—No fix listedCNA
  • Power 9 Systems VendorIBM Affected FW930; FW940; FW941; OP940 Fixed in — No fix listed CNA

CPE configurations NVD · 19

CPEVersionsRoleVendor
cpe:2.3:o:ibm:power9_system_firmware:*:*:*:*:*:*:*:*fw930.00 to before fw930.30; fw940.00 to before fw940.20VulnerableIBM
cpe:2.3:h:ibm:9008-22l:-:*:*:*:*:*:*:*not specified by NVDRunning onIBM
cpe:2.3:h:ibm:9009-22a:-:*:*:*:*:*:*:*not specified by NVDRunning onIBM
cpe:2.3:h:ibm:9009-41a:-:*:*:*:*:*:*:*not specified by NVDRunning onIBM
cpe:2.3:h:ibm:9009-42a:-:*:*:*:*:*:*:*not specified by NVDRunning onIBM
cpe:2.3:h:ibm:9040-mr9:-:*:*:*:*:*:*:*not specified by NVDRunning onIBM
cpe:2.3:h:ibm:9080-m9s:-:*:*:*:*:*:*:*not specified by NVDRunning onIBM
cpe:2.3:h:ibm:9223-22h:-:*:*:*:*:*:*:*not specified by NVDRunning onIBM
cpe:2.3:h:ibm:9223-42h:-:*:*:*:*:*:*:*not specified by NVDRunning onIBM
cpe:2.3:o:ibm:power9_system_firmware:*:*:*:*:*:*:*:*before fw950.00VulnerableIBM
  • cpe:2.3:o:ibm:power9_system_firmware:*:*:*:*:*:*:*:* Versions fw930.00 to before fw930.30; fw940.00 to before fw940.20 Vulnerable ·IBM
  • cpe:2.3:h:ibm:9008-22l:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·IBM
  • cpe:2.3:h:ibm:9009-22a:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·IBM
  • cpe:2.3:h:ibm:9009-41a:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·IBM
  • cpe:2.3:h:ibm:9009-42a:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·IBM
  • cpe:2.3:h:ibm:9040-mr9:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·IBM
  • cpe:2.3:h:ibm:9080-m9s:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·IBM
  • cpe:2.3:h:ibm:9223-22h:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·IBM
  • cpe:2.3:h:ibm:9223-42h:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·IBM
  • cpe:2.3:o:ibm:power9_system_firmware:*:*:*:*:*:*:*:* Versions before fw950.00 Vulnerable ·IBM
Show 9 more CPE
CPEVersionsRoleVendor
cpe:2.3:h:ibm:9009-22g:-:*:*:*:*:*:*:*not specified by NVDRunning onIBM
cpe:2.3:h:ibm:9009-41g:-:*:*:*:*:*:*:*not specified by NVDRunning onIBM
cpe:2.3:h:ibm:9009-42g:-:*:*:*:*:*:*:*not specified by NVDRunning onIBM
cpe:2.3:h:ibm:9223-22s:-:*:*:*:*:*:*:*not specified by NVDRunning onIBM
cpe:2.3:h:ibm:9223-42s:-:*:*:*:*:*:*:*not specified by NVDRunning onIBM
cpe:2.3:o:ibm:scale-out_lc_system_firmware:*:*:*:*:*:*:*:*before op940.20VulnerableIBM
cpe:2.3:h:ibm:8335-gth:-:*:*:*:*:*:*:*not specified by NVDRunning onIBM
cpe:2.3:h:ibm:8335-gtx:-:*:*:*:*:*:*:*not specified by NVDRunning onIBM
cpe:2.3:h:ibm:9183-22x:-:*:*:*:*:*:*:*not specified by NVDRunning onIBM
  • cpe:2.3:h:ibm:9009-22g:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·IBM
  • cpe:2.3:h:ibm:9009-41g:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·IBM
  • cpe:2.3:h:ibm:9009-42g:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·IBM
  • cpe:2.3:h:ibm:9223-22s:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·IBM
  • cpe:2.3:h:ibm:9223-42s:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·IBM
  • cpe:2.3:o:ibm:scale-out_lc_system_firmware:*:*:*:*:*:*:*:* Versions before op940.20 Vulnerable ·IBM
  • cpe:2.3:h:ibm:8335-gth:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·IBM
  • cpe:2.3:h:ibm:8335-gtx:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·IBM
  • cpe:2.3:h:ibm:9183-22x:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·IBM

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-20487
  2. 2026-10-03 Alias added: GHSA-gwjp-78rh-pcgc

References

Advisory 1

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences