CVE-2024-39420 [High] | Security Vulnerability in Acrobat

Acrobat Reader versions 20.005.30636, 24.002.21005, 24.001.30159, 20.005.30655, 24.002.20965, 24.002.20964, 24.001.30123, 24.003.20054 and earlier are affected by a Time-of-check Time-of-use (TOCTOU) Race Condition vulnerability that could lead to arbitrary code execution. This vulnerability arises when the timing of actions changes the state of a resource between the checking of a condition and the use of the resource, allowing an attacker to manipulate the resource in a harmful way. Exploitation of this issue requires user interaction in that a victim must open a malicious file.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-27	3.45%	3.49%	+0.04%
2	2026-06-15	1.56%	3.45%	+1.89%
3	2026-04-18	—	1.56%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-27

3.45%

3.49%

+0.04%

2026-06-15

1.56%

3.45%

+1.89%

2026-04-18

—

1.56%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
7.0	3.1	HIGH	`CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H` Click to expand Attack vector (AV:L) They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by. Attack complexity (AC:H) Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work. Privileges required (PR:N) No account or special rights needed—anonymous or random user is enough. User interaction (UI:R) A real person has to do something—click, install, enable—otherwise it doesn’t land. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	1.0	5.9	[email protected]
7.0	3.1	HIGH	`CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H` Click to expand Attack vector (AV:L) They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by. Attack complexity (AC:H) Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work. Privileges required (PR:N) No account or special rights needed—anonymous or random user is enough. User interaction (UI:R) A real person has to do something—click, install, enable—otherwise it doesn’t land. Scope (S:U) Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems. Confidentiality (C:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	1.0	5.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

7.0

3.1

HIGH

CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand

Attack vector (AV:L): They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:H): Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N): No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R): A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

1.0

5.9

[email protected]

7.0

3.1

HIGH

CVSS:3.1/AV:L/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand

Attack vector (AV:L): They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:H): Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N): No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R): A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U): Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

1.0

5.9

[email protected]

Affected software / configurations for CVE-2024-39420

Vendor	Product	Version	Raw CPE
adobe	acrobat	>= 20.001.30005, < 20.005.30655	cpe:2.3:a:adobe:acrobat:::::classic:::*
adobe	acrobat	>= 24.001.20604, < 24.001.30159	cpe:2.3:a:adobe:acrobat:::::classic:::*
adobe	acrobat_dc	>= 15.008.20082, < 24.002.21005	cpe:2.3:a:adobe:acrobat_dc:::::continuous:::*
adobe	acrobat_reader	>= 20.001.3005, < 20.005.30655	cpe:2.3:a:adobe:acrobat_reader:::::classic:::*
adobe	acrobat_reader_dc	>= 15.008.20082, < 24.002.21005	cpe:2.3:a:adobe:acrobat_reader_dc:::::continuous:::*

References for CVE-2024-39420

URL	Tags
https://helpx.adobe.com/security/products/acrobat/apsb24-70.html
https://www.talosintelligence.com/vulnerability_reports/TALOS-2024-2011

URL

CVE-2024-39420 | Acrobat Reader | Time-of-check Time-of-use (TOCTOU) Race Condition (CWE-367)

Exploit prediction scoring system (EPSS) score for CVE-2024-39420

Common vulnerability scoring system (CVSS) metrics for CVE-2024-39420

Weakness enumeration for CVE-2024-39420

Affected software / configurations for CVE-2024-39420

References for CVE-2024-39420