UPX 4.0.0 Mach-O File miniacc.h acc_ua_get_be32 heap-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.5$0-$5k0.00

Summaryinfo

A vulnerability was found in UPX 4.0.0. It has been declared as critical. Affected by this issue is the function acc_ua_get_be32 of the file miniacc.h of the component Mach-O File Handler. The manipulation results in heap-based overflow. This vulnerability was named CVE-2020-27799. The attack may be performed from remote. There is no available exploit.

Detailsinfo

A vulnerability, which was classified as critical, was found in UPX 4.0.0. Affected is the function acc_ua_get_be32 of the file miniacc.h of the component Mach-O File Handler. The manipulation with an unknown input leads to a heap-based overflow vulnerability. CWE is classifying the issue as 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(). This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

A heap-based buffer over-read was discovered in the acc_ua_get_be32 function in miniacc.h in UPX 4.0.0 via a crafted Mach-O file.

The weakness was presented 08/26/2022 as 391. The advisory is available at github.com. This vulnerability is traded as CVE-2020-27799 since 10/27/2020. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (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.

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Productinfo

Name

Version

License

Website

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

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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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: 🔍

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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: 391
Status: Confirmed

CVE: CVE-2020-27799 (🔍)
GCVE (CVE): GCVE-0-2020-27799
GCVE (VulDB): GCVE-100-207318

Entryinfo

Created: 08/26/2022 09:06
Updated: 04/11/2025 16:34
Changes: 08/26/2022 09:06 (40), 04/11/2025 16:34 (26)
Complete: 🔍
Cache ID: 216::103

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