How severe is CVE-2021-43448?

CVE-2021-43448 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2021-43448 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-43448?

CVE-2021-43448 affects Onlyoffice Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-43448?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-43448 published?

CVE-2021-43448 was published on 2023-01-23 and last updated on 2026-06-17.

CVE-2021-43448

CVE-2021-43448 is a medium-severity vulnerability in Onlyoffice Server with a CVSS 3.x base score of 5.3. 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 1% (59th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Onlyoffice Server
Published: 2023-01-23
Last modified: 2026-06-17

Description

ONLYOFFICE all versions as of 2021-11-08 is vulnerable to Improper Input Validation. A lack of input validation can allow an attacker to spoof the names of users who interact with a document, if the document id is known.

Frequently asked questions

What is CVE-2021-43448?: ONLYOFFICE all versions as of 2021-11-08 is vulnerable to Improper Input Validation. A lack of input validation can allow an attacker to spoof the names of users who interact with a document, if the document id is known.
How severe is CVE-2021-43448?: CVE-2021-43448 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2021-43448 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (59th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-43448?: CVE-2021-43448 affects Onlyoffice Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-43448?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-43448 published?: CVE-2021-43448 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-2021-43447 — High (CVSS 7.5): ONLYOFFICE all versions as of 2021-11-08 is affected by Incorrect Access Control. An authentication bypass in the…
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…

All CVEs affecting Onlyoffice Server →

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