How severe is CVE-2021-43447?

CVE-2021-43447 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2021-43447 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-43447?

CVE-2021-43447 affects Onlyoffice Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-43447?

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-2021-43447 published?

CVE-2021-43447 was published on 2023-01-23 and last updated on 2026-06-17.

CVE-2021-43447

CVE-2021-43447 is a high-severity vulnerability in Onlyoffice Server with a CVSS 3.x base score of 7.5. 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-306.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (69th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-306
Affected product: Onlyoffice Server
Published: 2023-01-23
Last modified: 2026-06-17

Description

ONLYOFFICE all versions as of 2021-11-08 is affected by Incorrect Access Control. An authentication bypass in the document editor allows attackers to edit documents without authentication.

Frequently asked questions

What is CVE-2021-43447?: ONLYOFFICE all versions as of 2021-11-08 is affected by Incorrect Access Control. An authentication bypass in the document editor allows attackers to edit documents without authentication.
How severe is CVE-2021-43447?: CVE-2021-43447 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2021-43447 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (69th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-43447?: CVE-2021-43447 affects Onlyoffice Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-43447?: 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-2021-43447 published?: CVE-2021-43447 was published on 2023-01-23 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:onlyoffice:server:*:*:*:*:*:*:*:*

More vulnerabilities in Onlyoffice Server

CVE-2021-43445 — Critical (CVSS 9.8): ONLYOFFICE all versions as of 2021-11-08 is affected by Incorrect Access Control. An attacker can authenticate with the…
CVE-2021-43449 — High (CVSS 8.1): ONLYOFFICE all versions as of 2021-11-08 is vulnerable to Server-Side Request Forgery (SSRF). The document editor…
CVE-2021-43444 — High (CVSS 7.5): ONLYOFFICE all versions as of 2021-11-08 is affected by Incorrect Access Control. Signed document download URLs can be…
CVE-2021-43446 — Medium (CVSS 6.1): ONLYOFFICE all versions as of 2021-11-08 is vulnerable to Cross Site Scripting (XSS). The "macros" feature of the…
CVE-2021-43448 — Medium (CVSS 5.3): ONLYOFFICE all versions as of 2021-11-08 is vulnerable to Improper Input Validation. A lack of input validation can…

All CVEs affecting Onlyoffice Server →

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