Uninitialized Pointer Freeing Vulnerability in SKALE sgxwallet 1.58.3

CVE-2021-36219 · CRITICAL Severity

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

An issue was discovered in SKALE sgxwallet 1.58.3. The provided input for ECALL 14 triggers a branch in trustedEcdsaSign that frees a non-initialized pointer from the stack. An attacker can chain multiple enclave calls to prepare a stack that contains a valid address. This address is then freed, resulting in compromised integrity of the enclave. This was resolved after v1.58.3 and not reproducible in sgxwallet v1.77.0.

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