CVE-2026-75900

An out-of-bounds read vulnerability was found in swtpm's SWTPM_NVRAM_CheckHeader() function. The entry guard checks the buffer length against sizeof(bh), where bh is a pointer, instead of sizeof(*bh), the actual struct size. This allows an undersized buffer to pass validation, causing a 2-byte heap overread on 64-bit systems (6 bytes on 32-bit) when accessing the totlen field. This may cause daemon termination on some platforms and leaks heap data to the log.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 4.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-75900
https://bugzilla.redhat.com/show_bug.cgi?id=2517910

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-19 08:17

Updated : 2026-08-21 20:16

NVD link : CVE-2026-75900

Mitre link : CVE-2026-75900

CVE.ORG link : CVE-2026-75900

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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