Exploited

CVE-2023-21608

Adobe Acrobat / Reader · Office, PDF and utilities

Adobe Acrobat and Reader Use-After-Free Vulnerability

At a glance

Exploited. Added to CISA’s catalog of exploited vulnerabilities on October 10, 2023.

Affected product: Adobe Acrobat / Reader (category Office, PDF and utilities, indicative classification). Name in CISA’s catalog: Adobe Acrobat and Reader.

What should I do?

Apply the patches or mitigations from Adobe; if none are available, stop using the product.

Deadline set by CISA for US federal agencies: 21 days (due October 31, 2023). It only binds those agencies, but it is a useful measure of urgency.

Adobe security advisories page (general page, not the advisory for this vulnerability)
The vendor’s specific advisory is listed in the NVD references: CVE-2023-21608 on the NVD website.

Original text of the required action (CISA)

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

Timeline

January 18, 2023 Vulnerability published Publication date (NVD)
October 10, 2023 Exploitation confirmed Added to CISA’s KEV catalog
October 31, 2023 CISA deadline Remediation deadline set for US federal agencies

The facts, with their sources

Exploitation confirmed: Yes, on October 10, 2023 Date added to the catalog of exploited vulnerabilities. Exploitation itself may have started earlier. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Ransomware: No known use to date That does not guarantee it is not being used: the information is not public. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Hunt for compromise: Not requested by CISA Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CISA required action: Apply the patches or mitigations from Adobe; if none are available, stop using the product. Rewritten by this site from CISA’s original text. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CISA deadline: October 31, 2023, 21 days Set for US federal agencies: a measure of urgency, not an obligation elsewhere. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Vulnerability published: January 18, 2023 Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC
Product according to CISA: Adobe Acrobat and Reader Filed by this site under “Office, PDF and utilities” (indicative classification). Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CVSS vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Technical detail of the score: attack vector, complexity, impact. Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC

Severity and activity

7.8 / 10 CVSS severity: high

Score from the vendor or CISA, relayed by the NVD. Collected Sep 29, 2026.

— Probability of exploitation in the next 30 days (EPSS)

FIRST’s EPSS model. Since exploitation is already confirmed, this figure is mostly useful to compare activity. Collected Sep 29, 2026.

Description

Adobe Acrobat Reader versions 22.003.20282 (and earlier), 22.003.20281 (and earlier) and 20.005.30418 (and earlier) are affected by a Use After Free vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.

Adobe Acrobat and Reader contains a use-after-free vulnerability that allows for code execution in the context of the current user.

Summary from CISA (KEV catalog).

CERT-FR advisories

No advisory among the latest CERT-FR publications this site follows. That does not mean there are none.

Information reused under the Open Licence 2.0 (Etalab); the date of last update is shown for each advisory. This site is neither affiliated with nor endorsed by ANSSI.

Sources for this page

CISA KEV catalog: exploitation, date added, required action, deadline, ransomware.
NVD (NIST): CVSS severity, publication date, description, vendor references.
EPSS (FIRST): probability of exploitation.
CERT-FR: advisories and alerts (in French).
Brand and category: indicative classification by this site (method).