How severe is GHSA-99p8-9p2c-49j4?

GHSA-99p8-9p2c-49j4 has a CVSS score of 4.3/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-99p8-9p2c-49j4?

GHSA-99p8-9p2c-49j4 affects the following packages: onionshare-cli (PyPI). Ecosystems affected: PyPI.

How do I fix GHSA-99p8-9p2c-49j4?

Update onionshare-cli to 2.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-99p8-9p2c-49j4 is resolved across your whole dependency graph.

How do I detect GHSA-99p8-9p2c-49j4 in my PyPI dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for onionshare-cli. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate GHSA-99p8-9p2c-49j4 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against GHSA-99p8-9p2c-49j4?

O3 pinpoints whether GHSA-99p8-9p2c-49j4 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-99p8-9p2c-49j4 actively exploited in the wild?

No public exploit code has been indexed for GHSA-99p8-9p2c-49j4 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-99p8-9p2c-49j4?

GHSA-99p8-9p2c-49j4 has an EPSS (Exploit Prediction Scoring System) score of 0.8%, placing it in the 53th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-99p8-9p2c-49j4?

GHSA-99p8-9p2c-49j4 is classified as Improper Authentication (CWE-287). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-99p8-9p2c-49j4 published, and has it been updated?

GHSA-99p8-9p2c-49j4 was published on January 21, 2022 and was last updated on October 8, 2024. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐍 PyPI

GHSA-99p8-9p2c-49j4

MEDIUM

Improper Access Control in Onionshare

Also known asCVE-2022-21695PYSEC-2022-46

Published

Jan 21, 2022

Updated

Oct 8, 2024

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

0.8%probability of exploitation in next 30 days

Lower Risk53th percentile+0.57%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

1 pkg affected

🐍onionshare-cli

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.

Description

Between September 26, 2021 and October 8, 2021, Radically Open Security conducted a penetration test of OnionShare 2.4, funded by the Open Technology Fund's Red Team lab. This is an issue from that penetration test.

Vulnerability ID: OTF-009
Vulnerability type: Improper Access Control
Threat level: Low

Description:

Authenticated users (or unauthenticated in public mode) can send messages without being visible in the list of chat participants.

Technical description:

Prerequisites:

Existing chatroom
Access to the chatroom (Public or known Private Key)
Either a modified frontend client or manual requests from burp/curl

If a user opens the chatroom without emitting the join message he will not be present in session.users[x] list. Therefore there is no listing in the frontend and no chat participant knows another party joined the chat. It is still possible to send messages in the chatroom.

If a user decides to abuse OTF-003 (page 22) he can impersonate messages from existing users; others would not be able to distinguish original and faked messages. This is also a prerequisite for OTF-004 (page 19).

Impact:

An adversary with access to the chat environment can send messages to the chat without being visible in the list of chat participants.

Recommendation:

Allow chat access only after emission of the join event.
Implement proper session handling.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`onionshare-cli`	≥ 2.3&&< 2.5	2.5

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for onionshare-cli. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update onionshare-cli to 2.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-99p8-9p2c-49j4 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-99p8-9p2c-49j4 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-99p8-9p2c-49j4. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Between September 26, 2021 and October 8, 2021, [Radically Open Security](https://www.radicallyopensecurity.com/) conducted a penetration test of OnionShare 2.4, funded by the Open Technology Fund's [Red Team lab](https://www.opentech.fund/labs/red-team-lab/). This is an issue from that penetration test. - Vulnerability ID: OTF-009 - Vulnerability type: Improper Access Control - Threat level: Low ## Description: Authenticated users (or unauthenticated in public mode) can send messages without being visible in the list of chat participants. ## Technical description: Prerequisites: - Exist

O3 Security · Impact-Aware SCA

Is GHSA-99p8-9p2c-49j4 in your dependencies?

O3 detects GHSA-99p8-9p2c-49j4 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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