How severe is CVE-2021-42721?

CVE-2021-42721 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-2021-42721 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-42721?

CVE-2021-42721 affects Adobe Media Encoder. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-42721?

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-2021-42721 published?

CVE-2021-42721 was published on 2021-11-16 and last updated on 2026-06-17.

CVE-2021-42721

CVE-2021-42721 is a high-severity vulnerability in Adobe Media Encoder 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-416.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 9.3
EPSS exploit prediction: 4% (88th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: Adobe Media Encoder
Published: 2021-11-16
Last modified: 2026-06-17

Description

Acrobat Bridge versions 11.1.1 and earlier are affected by a use-after-free vulnerability in the processing of Format event actions 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-2021-42721?: Acrobat Bridge versions 11.1.1 and earlier are affected by a use-after-free vulnerability in the processing of Format event actions 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-2021-42721?: CVE-2021-42721 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-2021-42721 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-42721?: CVE-2021-42721 affects Adobe Media Encoder. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-42721?: 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-2021-42721 published?: CVE-2021-42721 was published on 2021-11-16 and last updated on 2026-06-17.

References

https://helpx.adobe.com/security/products/bridge/apsb21-94.html

Affected products (1)

cpe:2.3:a:adobe:media_encoder:*:*:*:*:*:*:*:*

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