Adobe Acrobat Reader 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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7.4$5k-$25k0.00

Summaryinfo

A vulnerability has been found in Adobe Acrobat Reader up to 2017.011.30188/2020.001.30018/2020.013.20074 and classified as critical. This affects an unknown part. Performing a manipulation results in heap-based overflow. This vulnerability is cataloged as CVE-2021-21017. It is possible to initiate the attack remotely. Furthermore, there is an exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Adobe Acrobat Reader up to 2017.011.30188/2020.001.30018/2020.013.20074 (Document Reader Software). It has been classified as critical. This affects an unknown part. 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.

The weakness was shared 02/12/2021. The advisory is shared at helpx.adobe.com. This vulnerability is uniquely identified as CVE-2021-21017. It demands that the victim is doing some kind of user interaction. Technical details are unknown but an exploit is available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 02/13/2025).

It is declared as attacked. The CISA Known Exploited Vulnerabilities Catalog lists this issue since 11/03/2021 with a due date of 11/17/2021:

Apply updates per vendor instructions.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Zero-Day.cz (606). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.6
VulDB Meta Temp Score: 7.4

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 8.8
CNA Vector (Adobe Systems Incorporated): 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

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

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Attacked

EPSS Score: 🔍
EPSS Percentile: 🔍

KEV Added: 🔍
KEV Due: 🔍
KEV Remediation: 🔍
KEV Ransomware: 🔍
KEV Notice: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Zero-Day.cz: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

12/18/2020 🔍
02/12/2021 +56 days 🔍
02/12/2021 +0 days 🔍
05/04/2025 +1542 days 🔍

Sourcesinfo

Vendor: adobe.com

Advisory: helpx.adobe.com
Status: Confirmed

CVE: CVE-2021-21017 (🔍)
GCVE (CVE): GCVE-0-2021-21017
GCVE (VulDB): GCVE-100-169809
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 02/12/2021 11:35
Updated: 05/04/2025 06:18
Changes: 02/12/2021 11:35 (37), 02/28/2021 14:09 (5), 02/28/2021 14:13 (8), 04/21/2024 08:33 (26), 06/30/2024 07:19 (2), 09/11/2024 23:15 (1), 02/13/2025 23:59 (12), 05/04/2025 06:18 (3)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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