CVE-2026-6727: Medium severity Microsoft Windows 11 vulnerability
A timing side-channel vulnerability exists in the RSA OAEP decryption implementation. A privileged local attacker with access to the TPM command interface may be able to exploit timing differences to recover information that could allow decryption of ciphertexts encrypted to TPM-managed RSA keys, including the RSA Endorsement Key (EK), including import blobs, credential blobs, and session salts. Under certain conditions, this may also enable the forgery of TPM 2.0 attestations. Refer to TCGVRT0011.
Other sources
CVE-2026-6727 is an Information Disclosure vulnerability in the TPM 2.0 reference implementation involving an RSA OAEP timing side channel. MITRE assigned this CVE on behalf of the Trusted Computing Group. This document incorporates updates to Microsoft Windows that address this vulnerability. Please see CVE-2026-6727 for more information.
— Microsoft
MITRE: CVE-2026-6727 TPM 2.0 RSA OAEP Timing Side-Channel Vulnerability
— Microsoft
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.22631.7517Patch KB5120240 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.14393.9418Patch KB5120418 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.28000.2704Patch KB5121000 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26100.9168Fixed in 10.0.26100.9106Patch KB5120994 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.19045.7663Patch KB5120249 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26200.9168Fixed in 10.0.26100.9106Patch KB5120994 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26100.9168Fixed in 10.0.26000.9106Patch KB5120994 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.26100.33296Fixed in 10.0.26100.33222Patch KB5120228 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.19044.7663Patch KB5120249 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.20348.5499Fixed in 10.0.20348.5440Patch KB5120229 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 10.0.17763.9115Patch KB5120238
Event History
Frequently Asked Questions
What is the severity of CVE-2026-6727?
CVE-2026-6727 has a risk score of 44, indicating a high severity level.
How do I fix CVE-2026-6727?
To fix CVE-2026-6727, ensure you are using the latest version of the TCG TPM 2.0 software that addresses this vulnerability.
Who can exploit CVE-2026-6727?
CVE-2026-6727 can be exploited by a privileged local attacker with access to the TPM command interface.
What information can be compromised by CVE-2026-6727?
CVE-2026-6727 may allow attackers to recover information that could lead to decryption of ciphertexts encrypted to TPM-managed RSA keys.
Where can I find more technical details about CVE-2026-6727?
Technical details about CVE-2026-6727 can be found in advisories and guidance published by the Trusted Computing Group.