How severe is CVE-2021-41868?

CVE-2021-41868 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-2021-41868 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-41868?

CVE-2021-41868 affects Onionshare. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-41868?

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-2021-41868 published?

CVE-2021-41868 was published on 2021-10-04 and last updated on 2026-06-17.

CVE-2021-41868

CVE-2021-41868 is a critical-severity vulnerability in Onionshare 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.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 2% (81st percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Onionshare
Published: 2021-10-04
Last modified: 2026-06-17

Description

OnionShare 2.3 before 2.4 allows remote unauthenticated attackers to upload files on a non-public node when using the --receive functionality.

Frequently asked questions

What is CVE-2021-41868?: OnionShare 2.3 before 2.4 allows remote unauthenticated attackers to upload files on a non-public node when using the --receive functionality.
How severe is CVE-2021-41868?: CVE-2021-41868 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-2021-41868 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (81st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-41868?: CVE-2021-41868 affects Onionshare. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-41868?: 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-2021-41868 published?: CVE-2021-41868 was published on 2021-10-04 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:onionshare:onionshare:*:*:*:*:*:*:*:*

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