Stack-based buffer overflow in tpm2-tss - CVE-2026-73983
Published: November 4, 2026
Vulnerability identifier: #VU159293
CSH Severity: Low
CVSS v4: 6.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-73983
CWE-ID: CWE-121
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a local user to cause a denial of service and corrupt adjacent stack memory.
The vulnerability exists due to a stack-based buffer overflow caused by unchecked PCRIndex values in the tpm2-tss FAPI firmware eventlog serialization callbacks when processing attacker-controlled firmware eventlogs. A local user can supply an eventlog containing PCRIndex = 32 or PCRIndex = 0xFFFFFFFF to trigger an out-of-bounds read and increment of recnum_tab, causing a process crash or corruption of adjacent stack memory.
Affected software
tpm2-tss
How to mitigate CVE-2026-73983
Install security update from vendor's website.
tpm2-tss - addressed in versions 4.1.4, 4.2.0