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TI-2021-08760 Aliases CVE-2021-27217GHSA-2xj6-87qq-8g95

An issue was discovered in the _send_secure_msg() function of Yubico yubihsm-shell…

Priority LOW 24CWE-125Published · Updated

Key facts

Attack vector
Network
Privileges required
High
User interaction
None
Attack complexity
High
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-125 and the CVSS impact.

Summary

An issue was discovered in the _send_secure_msg() function of Yubico yubihsm-shell through 2.0.3. The function does not correctly validate the embedded length field of an authenticated message received from the device. Out-of-bounds reads performed by aes_remove_padding() can crash the running process, depending on the memory layout. This could be used by an attacker to cause a client-side denial of service. The yubihsm-shell project is included in the YubiHSM 2 SDK product.

Why it matters now

EPSS 0.01595 75th percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
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
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:yubico:yubihsm-shell:*:*:*:*:*:*:*:*up to 2.0.3VulnerableYubico
  • cpe:2.3:a:yubico:yubihsm-shell:*:*:*:*:*:*:*:* Versions up to 2.0.3 Vulnerable ·Yubico

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-27217
  2. 2026-10-03 Alias added: GHSA-2xj6-87qq-8g95

References

Exploit 1

Advisory 2

  • TI-2020-14929 An issue was discovered in the _send_secure_msg() function of yubihsm-shell through 2.0.2. CVSS 3.1HIGH 7.5
  • TI-2020-14928 An issue was discovered in the yh_create_session() function of yubihsm-shell through… CVSS 3.1HIGH 7.5
  • TI-2021-12167 An issue was discovered in the _send_secure_msg() function of Yubico yubihsm-shell… CVSS 3.1MEDIUM 4.4

Sources

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