VYPR
Moderate severityNVD Advisory· Published Oct 4, 2021· Updated Aug 4, 2024

CVE-2021-41867

CVE-2021-41867

Description

An information disclosure vulnerability in OnionShare 2.3 before 2.4 allows remote unauthenticated attackers to retrieve the full list of participants of a non-public OnionShare node via the --chat feature.

AI Insight

LLM-synthesized narrative grounded in this CVE's description and references.

OnionShare 2.3 before 2.4 discloses chat participants to unauthenticated remote attackers via the --chat feature.

Vulnerability

OnionShare versions 2.3 before 2.4 are vulnerable to an information disclosure vulnerability in the --chat feature. When a non-public OnionShare node is configured with the --chat option, an unauthenticated remote attacker can retrieve the full list of participants. The issue was fixed in version 2.4 [1][3].

Exploitation

An attacker needs only network access to the Tor onion service of the victim's OnionShare instance. No authentication or user interaction is required. By sending crafted requests to the chat endpoint, the attacker can enumerate all participants connected to the non-public chat room [3].

Impact

Successful exploitation allows the attacker to learn the identities (presumably Tor onion addresses or usernames) of all participants in a supposedly private chat session. This violates the confidentiality of the chat participants and could expose the fact that certain individuals are communicating via OnionShare [1][3].

Mitigation

The vulnerability is fixed in OnionShare version 2.4 released in October 2021 [1][2]. Users should upgrade to version 2.4 or later. As a workaround, avoid using the --chat feature in non-public mode or ensure that the instance is only accessible by trusted parties via proper authentication [3]. The CVE is not listed in KEV.

AI Insight generated on May 21, 2026. Synthesized from this CVE's description and the cited reference URLs; citations are validated against the source bundle.

Affected packages

Versions sourced from the GitHub Security Advisory.

PackageAffected versionsPatched versions
onionshare-cliPyPI
>= 2.3, < 2.42.4

Affected products

2

Patches

0

No patches discovered yet.

Vulnerability mechanics

AI mechanics synthesis has not run for this CVE yet.

References

5

News mentions

0

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