UPX 4.0.0 Mach-O File bele.h get_le64 heap-based overflow

HistoryDiffrelatejsonxmlCTI

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.5	$0-$5k	0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in UPX 4.0.0. This vulnerability affects the function get_le64 of the file bele.h of the component Mach-O File Handler. Such manipulation leads to heap-based overflow. This vulnerability is referenced as CVE-2020-27801. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability was found in UPX 4.0.0 and classified as critical. Affected by this issue is the function get_le64 of the file bele.h of the component Mach-O File Handler. The manipulation with an unknown input leads to a heap-based overflow vulnerability. Using CWE to declare the problem leads to CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). Impacted is confidentiality, integrity, and availability. CVE summarizes:

A heap-based buffer over-read was discovered in the get_le64 function in bele.h in UPX 4.0.0 via a crafted Mach-O file.

The weakness was published 08/26/2022 as 394. The advisory is shared for download at github.com. This vulnerability is handled as CVE-2020-27801 since 10/27/2020. There are known technical details, but no exploit is available. The current price for an exploit might be approx. USD $0-$5k (estimation calculated on 04/11/2025).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Name

Version

4.0.0

License

free

Website

Product: https://github.com/upx/upx/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.5

VulDB Base Score: 7.3
VulDB Temp Score: 7.3
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

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💳	💳	💳	💳	💳	💳
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

10/27/2020 🔍
08/26/2022 +667 days 🔍
08/26/2022 +0 days 🔍
04/11/2025 +959 days 🔍

Sourcesinfo

Product: github.com

Advisory: 394
Status: Confirmed

CVE: CVE-2020-27801 (🔍)
GCVE (CVE): GCVE-0-2020-27801
GCVE (VulDB): GCVE-100-207320

Entryinfo

Created: 08/26/2022 09:07
Updated: 04/11/2025 16:34
Changes: 08/26/2022 09:07 (40), 10/02/2022 07:28 (11), 04/11/2025 16:34 (15)
Complete: 🔍
Cache ID: 216::103