Low severity · published Jul 6, 2026
CVE-2026-53763
OP-TEE has AES-GCM 32-bit integer overflow in length counters that breaks authentication guarantee
3.8
CVSS
0.2%
EPSS
No
On KEV
Description
OP-TEE is a Trusted Execution Environment (TEE) designed as companion to a non-secure Linux kernel running on Arm; Cortex-A cores using the TrustZone technology. Starting in version 3.0.0 and prior to version 4.11.0, 32-bit integer overflows in OP-TEE core's AES-GCM implementation cause the authentication tag to be computed with incorrect bit-length values after processing more than 512 megabytes of payload or Additional Authenticated Data (AAD). Version 4.11.0 contains a patch. No known workarounds are available.
CVSS vector
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:N
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 9% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
OP
optee_os · OP-TEE
>= 3.0.0, < 4.11.0 · source: vendor
OP
Op-tee · Trustedfirmware
3.0.0 through 4.10.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-53763
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-53763
Vendor Advisory
https://github.com/OP-TEE/optee_os/security/advisories/GHSA-fcm8-vjhf-6vqh
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