Source: optee-os Version: 4.5.0-1 Severity: grave Tags: security upstream X-Debbugs-Cc: [email protected], Debian Security Team <[email protected]>
Hi, The following vulnerability was published for optee-os. CVE-2025-46733[0]: | 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. In version 4.5.0, using a | specially crafted tee-supplicant binary running in REE userspace, an | attacker can trigger a panic in a TA that uses the libutee Secure | Storage API. Many functions in libutee, specifically those which | make up the Secure Storage API, will panic if a system call returns | an unexpected return code. This behavior is mandated by the TEE | Internal Core API specification. However, in OP-TEE’s | implementation, return codes of secure storage operations are passed | through unsanitized from the REE tee-supplicant, through the Linux | kernel tee-driver, through the OP-TEE kernel, back to libutee. Thus, | an attacker with access to REE userspace, and the ability to stop | tee-supplicant and replace it with their own process (generally | trivial for a root user, and depending on the way permissions are | set up, potentially available even to less privileged users) can run | a malicious tee-supplicant process that responds to storage requests | with unexpected response codes, triggering a panic in the requesting | TA. This is particularly dangerous for TAs built with | `TA_FLAG_SINGLE_INSTANCE` (corresponding to `gpd.ta.singleInstance` | and `TA_FLAG_INSTANCE_KEEP_ALIVE` (corresponding to | `gpd.ta.keepAlive`). The behavior of these TAs may depend on memory | that is preserved between sessions, and the ability of an attacker | to panic the TA and reload it with a clean memory space can | compromise the behavior of those TAs. A critical example of this is | the optee_ftpm TA. It uses the kept alive memory to hold PCR values, | which crucially must be non-resettable. An attacker who can trigger | a panic in the fTPM TA can reset the PCRs, and then extend them PCRs | with whatever they choose, falsifying boot measurements, accessing | sealed data, and potentially more. The impact of this issue depends | significantly on the behavior of affected TAs. For some, it could | manifest as a denial of service, while for others, like the fTPM TA, | it can result in the disclosure of sensitive data. Anyone running | the fTPM TA is affected, but similar attacks may be possible on | other TAs that leverage the Secure Storage API. A fix is available | in commit 941a58d78c99c4754fbd4ec3079ec9e1d596af8f. If you fix the vulnerability please also make sure to include the CVE (Common Vulnerabilities & Exposures) id in your changelog entry. For further information see: [0] https://security-tracker.debian.org/tracker/CVE-2025-46733 https://www.cve.org/CVERecord?id=CVE-2025-46733 [1] https://github.com/OP-TEE/optee_os/security/advisories/GHSA-f35r-hm2m-p6c3 [2] https://github.com/OP-TEE/optee_os/commit/941a58d78c99c4754fbd4ec3079ec9e1d596af8f Regards, Salvatore
