How severe is CVE-2023-26421?

CVE-2023-26421 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-26421 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (90th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-26421?

CVE-2023-26421 primarily affects Adobe Acrobat. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-26421?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2023-26421 published?

CVE-2023-26421 was published on 2023-04-12 and last updated on 2026-06-17.

CVE-2023-26421

CVE-2023-26421 is a high-severity vulnerability in Adobe Acrobat with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-191.

Key facts

Severity: High (CVSS 3.x base score 7.8)
EPSS exploit prediction: 5% (90th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-191
Affected product: Adobe Acrobat
Published: 2023-04-12
Last modified: 2026-06-17

Description

Adobe Acrobat Reader versions 23.001.20093 (and earlier) and 20.005.30441 (and earlier) are affected by an Integer Underflow or Wraparound 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.

Frequently asked questions

What is CVE-2023-26421?: Adobe Acrobat Reader versions 23.001.20093 (and earlier) and 20.005.30441 (and earlier) are affected by an Integer Underflow or Wraparound 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.
How severe is CVE-2023-26421?: CVE-2023-26421 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-26421 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-26421?: CVE-2023-26421 primarily affects Adobe Acrobat. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-26421?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2023-26421 published?: CVE-2023-26421 was published on 2023-04-12 and last updated on 2026-06-17.

References

https://helpx.adobe.com/security/products/acrobat/apsb23-24.html

Affected products (4)

cpe:2.3:a:adobe:acrobat:*:*:*:*:classic:*:*:*
cpe:2.3:a:adobe:acrobat_dc:*:*:*:*:continuous:*:*:*
cpe:2.3:a:adobe:acrobat_reader:*:*:*:*:classic:*:*:*
cpe:2.3:a:adobe:acrobat_reader_dc:*:*:*:*:continuous:*:*:*

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