How severe is CVE-2020-11536?

CVE-2020-11536 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2020-11536 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-11536?

CVE-2020-11536 affects Onlyoffice Document Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-11536?

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

When was CVE-2020-11536 published?

CVE-2020-11536 was published on 2020-04-15 and last updated on 2026-06-17.

CVE-2020-11536

CVE-2020-11536 is a critical-severity vulnerability in Onlyoffice Document Server with a CVSS 3.x base score of 9.8. 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-20.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (83rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Onlyoffice Document Server
Published: 2020-04-15
Last modified: 2026-06-17

Description

An issue was discovered in ONLYOFFICE Document Server 5.5.0. An attacker can craft a malicious .docx file, and exploit the unzip function to rewrite a binary and remotely execute code on a victim's server.

Frequently asked questions

What is CVE-2020-11536?: An issue was discovered in ONLYOFFICE Document Server 5.5.0. An attacker can craft a malicious .docx file, and exploit the unzip function to rewrite a binary and remotely execute code on a victim's server.
How severe is CVE-2020-11536?: CVE-2020-11536 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2020-11536 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-11536?: CVE-2020-11536 affects Onlyoffice Document Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-11536?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2020-11536 published?: CVE-2020-11536 was published on 2020-04-15 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:onlyoffice:document_server:5.5.0:*:*:*:*:*:*:*

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