Integer Overflow in radare2 Due to core_anal_bytes

Executive Summary

This vulnerability is a signed integer overflow in the radare2 tool, specifically in the function core_anal_bytes within the file libr/core/cmd_anal.inc.c. It occurs when the aos command processes a large input value (268435456), which is multiplied by 8 without validating the input length. This multiplication causes the value to exceed the maximum limit for a signed integer, resulting in an overflow. The issue arises because the code does not check if the input is within safe bounds before performing arithmetic operations.

The overflow is detected by UndefinedBehaviorSanitizer (UBSan) and can be triggered locally by an attacker. A proof-of-concept script and test binary exist to reproduce the issue. The vulnerability originates in the cmd_anal_opcode function and propagates through the radare2 command execution system.

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Impact Analysis

This vulnerability can lead to unexpected behavior or crashes in the radare2 tool when processing specially crafted inputs locally. Because it is an integer overflow, it may allow an attacker with local access to manipulate the program's execution flow or cause denial of service by crashing the application.

The exploit has been publicly disclosed, so attackers may use it to compromise systems where radare2 is installed and used without the patch.

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Detection Guidance

This vulnerability can be detected by reproducing the integer overflow condition in the radare2 tool using the provided proof-of-concept script and test binary.

Specifically, running the `aos` command in radare2 with a large input value (268435456) triggers the overflow in the `core_anal_bytes` function.

You can use the provided `run-overflow.sh` script along with the `onebyte.bin` test binary to reproduce and detect the overflow condition.

Additionally, using UndefinedBehaviorSanitizer (UBSan) during radare2 execution can help detect the signed integer overflow at runtime.

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Mitigation Strategies

The recommended immediate step to mitigate this vulnerability is to install the patch provided by the radare2 developers that addresses the integer overflow issue.

The patch involves validating input lengths before performing arithmetic operations or using checked arithmetic to prevent overflow.

Since the attack requires local access, restricting local user permissions and access to radare2 may reduce risk until the patch is applied.

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Compliance Impact

The provided information does not specify any direct impact of this vulnerability on compliance with common standards and regulations such as GDPR or HIPAA.

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