How severe is CVE-2021-42727?

CVE-2021-42727 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-2021-42727 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 39% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-42727?

CVE-2021-42727 affects Adobe Robohelp Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-42727?

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-2021-42727 published?

CVE-2021-42727 was published on 2021-11-22 and last updated on 2026-06-17.

CVE-2021-42727

CVE-2021-42727 is a high-severity vulnerability in Adobe Robohelp Server with a CVSS 3.x base score of 7.8. Its EPSS exploit-prediction score of 39% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-787.

Key facts

Severity: High (CVSS 3.x base score 7.8)
CVSS v2: 9.3
EPSS exploit prediction: 39% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Adobe Robohelp Server
Published: 2021-11-22
Last modified: 2026-06-17

Description

Adobe Bridge 11.1.1 (and earlier) is affected by a stack overflow vulnerability due to insecure handling of a crafted file, potentially resulting in arbitrary code execution in the context of the current user. Exploitation requires user interaction in that a victim must open a crafted file in Bridge.

Frequently asked questions

What is CVE-2021-42727?: Adobe Bridge 11.1.1 (and earlier) is affected by a stack overflow vulnerability due to insecure handling of a crafted file, potentially resulting in arbitrary code execution in the context of the current user. Exploitation requires user interaction in that a victim must open a crafted file in Bridge.
How severe is CVE-2021-42727?: CVE-2021-42727 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-2021-42727 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 39% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-42727?: CVE-2021-42727 affects Adobe Robohelp Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-42727?: 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-2021-42727 published?: CVE-2021-42727 was published on 2021-11-22 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:robohelp_server:*:*:*:*:*:*:*:*

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