Adobe Acrobat Reader DC use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.3$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in Adobe Acrobat Reader DC up to 2017.011.30199/2020.004.30006/2021.005.20060. The affected element is an unknown function. Such manipulation leads to use after free. This vulnerability is documented as CVE-2021-39859. The attack needs to be performed locally. There is not any exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Adobe Acrobat Reader DC up to 2017.011.30199/2020.004.30006/2021.005.20060 (Document Reader Software) and classified as problematic. Affected by this issue is an unknown function. The manipulation with an unknown input leads to a use after free vulnerability. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality. CVE summarizes:

Acrobat Reader DC versions 2021.005.20060 (and earlier), 2020.004.30006 (and earlier) and 2017.011.30199 (and earlier) are affected by a Use After Free vulnerability that could lead to disclosure of sensitive memory. An attacker could leverage this vulnerability to bypass mitigations such as ASLR. Exploitation of this issue requires user interaction in that a victim must open a malicious file.

The weakness was released 09/06/2023 as apsb21-55. The advisory is shared for download at helpx.adobe.com. This vulnerability is handled as CVE-2021-39859 since 08/23/2021. There are neither technical details nor an exploit publicly available.

Upgrading eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.4
VulDB Meta Temp Score: 4.3

VulDB Base Score: 3.3
VulDB Temp Score: 3.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 5.5
CNA Vector (Adobe Systems Incorporated): 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

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: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

08/23/2021 🔍
09/06/2023 +744 days 🔍
09/06/2023 +0 days 🔍
09/06/2023 +0 days 🔍

Sourcesinfo

Vendor: adobe.com

Advisory: apsb21-55
Status: Confirmed

CVE: CVE-2021-39859 (🔍)
GCVE (CVE): GCVE-0-2021-39859
GCVE (VulDB): GCVE-100-239036

Entryinfo

Created: 09/06/2023 18:00
Changes: 09/06/2023 18:00 (49)
Complete: 🔍
Cache ID: 216::103

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