Out-of-bounds read in tpm2-tss - CVE-2026-73981
Published: November 4, 2026
Vulnerability identifier: #VU159289
CSH Severity: Low
CVSS v4: 6.7 [CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-73981
CWE-ID: CWE-125
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local privileged user to cause a denial of service by triggering an out-of-bounds heap read.
The vulnerability exists due to an out-of-bounds read caused by unchecked response lengths in Tss2_Sys_GetEncryptParam and its ESAPI consumer iesys_decrypt_param when processing TPM responses for an HMAC session with TPMA_SESSION_ENCRYPT set. A local privileged user can control a local software TPM transport and supply a forged response with an inflated parameter length and a valid response HMAC to cause a heap over-read that may crash the calling process.
Affected software
tpm2-tss
How to mitigate CVE-2026-73981
Install security update from vendor's website.
tpm2-tss - addressed in versions 4.1.4, 4.2.0