Adobe Acrobat Reader use after free

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 (≈)
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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.
8.1$5k-$25k0.00

Summaryinfo

A vulnerability classified as critical was found in Adobe Acrobat Reader up to 2017.011.30194/2020.001.30020/2021.001.20150. Affected is an unknown function. Executing a manipulation can lead to use after free. This vulnerability is tracked as CVE-2021-28550. The attack can be launched remotely. Moreover, an exploit is present. Upgrading the affected component is advised.

Detailsinfo

A vulnerability classified as critical was found in Adobe Acrobat Reader up to 2017.011.30194/2020.001.30020/2021.001.20150 (Document Reader Software). This vulnerability affects an unknown function. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was disclosed 09/02/2021 as apsb21-29. The advisory is shared for download at helpx.adobe.com. This vulnerability was named CVE-2021-28550. Successful exploitation requires user interaction by the victim. Technical details are unknown but an exploit is available. The current price for an exploit might be approx. USD $5k-$25k (estimation calculated on 09/13/2024).

It is declared as attacked. This issue was added on 11/03/2021 to the CISA Known Exploited Vulnerabilities Catalog 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 (628). Once again VulDB remains the best source for vulnerability data.

Productinfo

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.2
VulDB Meta Temp Score: 8.1

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

NVD Base Score: 8.8
NVD Vector: 🔍

CNA Base Score: 9.6
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: Use after free
CWE: CWE-416 / 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

03/16/2021 🔍
09/02/2021 +169 days 🔍
09/02/2021 +0 days 🔍
05/03/2025 +1339 days 🔍

Sourcesinfo

Vendor: adobe.com

Advisory: apsb21-29
Status: Confirmed

CVE: CVE-2021-28550 (🔍)
GCVE (CVE): GCVE-0-2021-28550
GCVE (VulDB): GCVE-100-181972
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 09/02/2021 22:47
Updated: 05/03/2025 12:22
Changes: 09/02/2021 22:47 (39), 09/09/2021 11:13 (2), 09/09/2021 11:20 (1), 04/21/2024 13:23 (26), 06/28/2024 00:04 (2), 07/29/2024 23:25 (28), 09/13/2024 11:48 (1), 05/03/2025 12:22 (3)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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