CVE-2026-82876

Phison PS3111-S11 controller firmware verifies RSA signatures using a public modulus embedded within the firmware image itself rather than anchored in immutable storage. Attackers can generate arbitrary RSA key pairs, sign modified firmware with the private key, embed the matching modulus in the signature segment, and the controller accepts the tampered firmware as valid.

CVSS v3 8.2 HIGH

8.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.5 / Impact : 6.0

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/trulycrisp/psychite
https://trulycrisp.github.io/drivefirmware/phison_s11/
https://www.vulncheck.com/advisories/phison-ps3111-s11-controller-firmware-signature-verification-bypass

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-31 11:16

Updated : 2026-09-10 15:47

NVD link : CVE-2026-82876

Mitre link : CVE-2026-82876

CVE.ORG link : CVE-2026-82876

JSON object : View

Products Affected

No product.

CWE

CWE-347

Improper Verification of Cryptographic Signature

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