CVE-2021-21042

Acrobat Reader DC Out-Of-Bounds Read Information Disclosure Vulnerability

Severity Score

6.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

*SSVC

Descriptions

Acrobat Reader DC versions 2020.013.20074 (and earlier), 2020.001.30018 (and earlier) and 2017.011.30188 (and earlier) are affected by an Out-of-bounds Read vulnerability that could lead to arbitrary disclosure of information in the memory stack. 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.

Las versiones 2020.013.20074 (y anteriores), 2020.001.30018 (y anteriores) y 2017.011.30188 (y anteriores) de Acrobat Reader DC están afectadas por una vulnerabilidad de lectura fuera de los límites que podría conducir a la divulgación arbitraria de información en la pila de memoria. Un atacante podría aprovechar esta vulnerabilidad para eludir mitigaciones como ASLR. La explotación de este problema requiere la interacción del usuario, ya que la víctima debe abrir un archivo malicioso

This vulnerability allows remote attackers to disclose sensitive information on affected installations of Adobe Acrobat Reader DC. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file.
The specific flaw exists within the handling of the File ID parameter in the PDF trailer. By performing actions in JavaScript, an attacker can disclose the base address of Annots.api. An attacker can leverage this in conjunction with other vulnerabilities to execute arbitrary code in the context of the current process.

*Credits: Mark Vincent Yason (@MarkYason)

CVSS Scores

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

None

Availability

None

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

None

Attack Vector

Network

Attack Complexity

Medium

Authentication

None

Confidentiality

Partial

Integrity

None

Availability

None

* Common Vulnerability Scoring System

SSVC

Decision:-

Exploitation

Automatable

Tech. Impact

* Organization's Worst-case Scenario

Timeline

2020-12-18 CVE Reserved
2021-02-10 CVE Published
2021-03-04 First Exploit
2024-09-16 CVE Updated
2024-09-25 EPSS Updated
---------- Exploited in Wild
---------- KEV Due Date

CWE

CWE-125: Out-of-bounds Read

CAPEC

References (3)

URL	Tag	Source

URL	Date	SRC
https://github.com/r1l4-i3pur1l4/CVE-2021-21042	2021-11-27
https://github.com/NattiSamson/CVE-2021-21042	2021-03-04

URL	Date	SRC

URL	Date	SRC
https://helpx.adobe.com/security/products/acrobat/apsb21-09.html	2023-11-07

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Adobe Search vendor "Adobe"	Acrobat Search vendor "Adobe" for product "Acrobat"	>= 17.0 <= 17.011.30188 Search vendor "Adobe" for product "Acrobat" and version " >= 17.0 <= 17.011.30188"	classic	Affected	in	Apple Search vendor "Apple"	Macos Search vendor "Apple" for product "Macos"	-	-	Safe
Adobe Search vendor "Adobe"	Acrobat Search vendor "Adobe" for product "Acrobat"	>= 17.0 <= 17.011.30188 Search vendor "Adobe" for product "Acrobat" and version " >= 17.0 <= 17.011.30188"	classic	Affected	in	Microsoft Search vendor "Microsoft"	Windows Search vendor "Microsoft" for product "Windows"	-	-	Safe
Adobe Search vendor "Adobe"	Acrobat Search vendor "Adobe" for product "Acrobat"	>= 20.0 <= 20.001.30018 Search vendor "Adobe" for product "Acrobat" and version " >= 20.0 <= 20.001.30018"	classic	Affected	in	Apple Search vendor "Apple"	Macos Search vendor "Apple" for product "Macos"	-	-	Safe
Adobe Search vendor "Adobe"	Acrobat Search vendor "Adobe" for product "Acrobat"	>= 20.0 <= 20.001.30018 Search vendor "Adobe" for product "Acrobat" and version " >= 20.0 <= 20.001.30018"	classic	Affected	in	Microsoft Search vendor "Microsoft"	Windows Search vendor "Microsoft" for product "Windows"	-	-	Safe
Adobe Search vendor "Adobe"	Acrobat Dc Search vendor "Adobe" for product "Acrobat Dc"	<= 20.013.20074 Search vendor "Adobe" for product "Acrobat Dc" and version " <= 20.013.20074"	continuous	Affected	in	Apple Search vendor "Apple"	Macos Search vendor "Apple" for product "Macos"	-	-	Safe
Adobe Search vendor "Adobe"	Acrobat Dc Search vendor "Adobe" for product "Acrobat Dc"	<= 20.013.20074 Search vendor "Adobe" for product "Acrobat Dc" and version " <= 20.013.20074"	continuous	Affected	in	Microsoft Search vendor "Microsoft"	Windows Search vendor "Microsoft" for product "Windows"	-	-	Safe
Adobe Search vendor "Adobe"	Acrobat Reader Search vendor "Adobe" for product "Acrobat Reader"	>= 17.0 <= 17.011.30188 Search vendor "Adobe" for product "Acrobat Reader" and version " >= 17.0 <= 17.011.30188"	classic	Affected	in	Apple Search vendor "Apple"	Macos Search vendor "Apple" for product "Macos"	-	-	Safe
Adobe Search vendor "Adobe"	Acrobat Reader Search vendor "Adobe" for product "Acrobat Reader"	>= 17.0 <= 17.011.30188 Search vendor "Adobe" for product "Acrobat Reader" and version " >= 17.0 <= 17.011.30188"	classic	Affected	in	Microsoft Search vendor "Microsoft"	Windows Search vendor "Microsoft" for product "Windows"	-	-	Safe
Adobe Search vendor "Adobe"	Acrobat Reader Search vendor "Adobe" for product "Acrobat Reader"	>= 20.0 <= 20.001.300183 Search vendor "Adobe" for product "Acrobat Reader" and version " >= 20.0 <= 20.001.300183"	classic	Affected	in	Apple Search vendor "Apple"	Macos Search vendor "Apple" for product "Macos"	-	-	Safe
Adobe Search vendor "Adobe"	Acrobat Reader Search vendor "Adobe" for product "Acrobat Reader"	>= 20.0 <= 20.001.300183 Search vendor "Adobe" for product "Acrobat Reader" and version " >= 20.0 <= 20.001.300183"	classic	Affected	in	Microsoft Search vendor "Microsoft"	Windows Search vendor "Microsoft" for product "Windows"	-	-	Safe
Adobe Search vendor "Adobe"	Acrobat Reader Dc Search vendor "Adobe" for product "Acrobat Reader Dc"	<= 20.013.20074 Search vendor "Adobe" for product "Acrobat Reader Dc" and version " <= 20.013.20074"	continuous	Affected	in	Apple Search vendor "Apple"	Macos Search vendor "Apple" for product "Macos"	-	-	Safe
Adobe Search vendor "Adobe"	Acrobat Reader Dc Search vendor "Adobe" for product "Acrobat Reader Dc"	<= 20.013.20074 Search vendor "Adobe" for product "Acrobat Reader Dc" and version " <= 20.013.20074"	continuous	Affected	in	Microsoft Search vendor "Microsoft"	Windows Search vendor "Microsoft" for product "Windows"	-	-	Safe