How severe is CVE-2021-41110?

CVE-2021-41110 has a CVSS 3.x base score of 9.1, rated critical 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 high.

Is CVE-2021-41110 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-41110?

CVE-2021-41110 affects Commonwl Cwlviewer. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-41110?

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-2021-41110 published?

CVE-2021-41110 was published on 2021-10-01 and last updated on 2026-06-17.

CVE-2021-41110

CVE-2021-41110 is a critical-severity vulnerability in Commonwl Cwlviewer with a CVSS 3.x base score of 9.1. 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-502.

Key facts

Severity: Critical (CVSS 3.x base score 9.1)
CVSS v2: 7.5
EPSS exploit prediction: 3% (84th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-502
Affected product: Commonwl Cwlviewer
Published: 2021-10-01
Last modified: 2026-06-17

Description

cwlviewer is a web application to view and share Common Workflow Language workflows. Versions prior to 1.3.1 contain a Deserialization of Untrusted Data vulnerability. Commit number f6066f09edb70033a2ce80200e9fa9e70a5c29de (dated 2021-09-30) contains a patch. There are no available workarounds aside from installing the patch. The SnakeYaml constructor, by default, allows any data to be parsed. To fix the issue the object needs to be created with a `SafeConstructor` object, as seen in the patch.

Frequently asked questions

What is CVE-2021-41110?: cwlviewer is a web application to view and share Common Workflow Language workflows. Versions prior to 1.3.1 contain a Deserialization of Untrusted Data vulnerability. Commit number f6066f09edb70033a2ce80200e9fa9e70a5c29de (dated 2021-09-30) contains a patch. There are no available workarounds aside from installing the patch. The SnakeYaml constructor, by default, allows any data to be parsed. To fix the issue the object needs to be created with a `SafeConstructor` object, as seen in the patch.
How severe is CVE-2021-41110?: CVE-2021-41110 has a CVSS 3.x base score of 9.1, rated critical 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 high.
Is CVE-2021-41110 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-41110?: CVE-2021-41110 affects Commonwl Cwlviewer. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-41110?: 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-2021-41110 published?: CVE-2021-41110 was published on 2021-10-01 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:commonwl:cwlviewer:*:*:*:*:*:*:*:*

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