CVE-2021-44078

Sandbox escape via incorrect memory-region comparison

Published Dec 26, 2021 · Updated Aug 4, 2024

Sandbox escape in Unicorn Engine before 2.0.0-rc5 allows local users to execute arbitrary code on the host from crafted sandbox code. The split_region function in uc.c compares a RAM-block offset with a guest physical address while partially unmapping uc_mem_map_ptr-backed memory, which can select the wrong block. Exploitation requires the ability to execute crafted code inside the target sandbox and can cross the sandbox boundary into host code execution.

CVSS severity8.1
High
EPSS probability0.53%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Sandbox escape in Unicorn Engine before 2.0.0-rc5 allows local users to execute arbitrary code on the host from crafted sandbox code. The split_region function in uc.c compares a RAM-block offset with a guest physical address while partially unmapping uc_mem_map_ptr-backed memory, which can select the wrong block. Exploitation requires the ability to execute crafted code inside the target sandbox and can cross the sandbox boundary into host code execution.

The record

CVE
CVE-2021-44078
Published
Dec 26, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-697
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 26, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.1NISTCVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
6.8NISTAV:L/AC:M/Au:N/C:C/I:C/A:C

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-697Incorrect Comparison

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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