What’s Vulnerable › Vulnerabilities

CVE-2021-44421

• Severity: medium (CVSS 5.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2022-03-10 · updated 2026-06-17
• Weakness: CWE-203

Description

The pointer-validation logic in util/mem_util.rs in Occlum before 0.26.0 for Intel SGX acts as a confused deputy that allows a local attacker to access unauthorized information via side-channel analysis.

Affected products

• Occlum Project Occlum: before 0.26.0 — fixed in 0.26.0

How to fix

Upgrade to a fixed version: Occlum Project Occlum 0.26.0. Check the vendor advisory for mitigations.

References

• https://github.com/occlum/occlum/blob/821ea843ae21037e6cff5268306d2da1fb131552/src/libos/src/util/mem_util.rs#L130
• https://github.com/occlum/occlum/blob/821ea843ae21037e6cff5268306d2da1fb131552/src/libos/src/util/mem_util.rs#L51
• https://github.com/occlum/occlum/commit/36918e42bf6732c4d3996bc99eb013eb6b90b249
• https://github.com/occlum/occlum/compare/0.25.0...v0.26.0
• https://github.com/occlum/occlum/blob/821ea843ae21037e6cff5268306d2da1fb131552/src/libos/src/util/mem_util.rs#L130
• https://github.com/occlum/occlum/blob/821ea843ae21037e6cff5268306d2da1fb131552/src/libos/src/util/mem_util.rs#L51
• https://github.com/occlum/occlum/commit/36918e42bf6732c4d3996bc99eb013eb6b90b249
• https://github.com/occlum/occlum/compare/0.25.0...v0.26.0

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