CVE-2022-21688

CVE-2022-21688 is a high-severity vulnerability in Onionshare 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-125.

Key facts

Description

OnionShare is an open source tool that lets you securely and anonymously share files, host websites, and chat with friends using the Tor network. Affected versions of the desktop application were found to be vulnerable to denial of service via an undisclosed vulnerability in the QT image parsing. Roughly 20 bytes lead to 2GB memory consumption and this can be triggered multiple times. To be abused, this vulnerability requires rendering in the history tab, so some user interaction is required. An adversary with knowledge of the Onion service address in public mode or with authentication in private mode can perform a Denial of Service attack, which quickly results in out-of-memory for the server. This requires the desktop application with rendered history, therefore the impact is only elevated. This issue has been patched in version 2.5.

Frequently asked questions

What is CVE-2022-21688?
OnionShare is an open source tool that lets you securely and anonymously share files, host websites, and chat with friends using the Tor network. Affected versions of the desktop application were found to be vulnerable to denial of service via an undisclosed vulnerability in the QT image parsing. Roughly 20 bytes lead to 2GB memory consumption and this can be triggered multiple times. To be abused, this vulnerability requires rendering in the history tab, so some user interaction is required. An adversary with knowledge of the Onion service address in public mode or with authentication in private mode can perform a Denial of Service attack, which quickly results in out-of-memory for the server. This requires the desktop application with rendered history, therefore the impact is only elevated. This issue has been patched in version 2.5.
How severe is CVE-2022-21688?
CVE-2022-21688 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 none, and availability high.
Is CVE-2022-21688 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-21688?
CVE-2022-21688 affects Onionshare. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2022-21688?
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-2022-21688 published?
CVE-2022-21688 was published on 2022-01-18 and last updated on 2026-06-17.

References

Affected products (1)

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