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. In affected versions the receive mode limits concurrent uploads to 100 per second and blocks other uploads in the same second, which can be triggered by a simple script. An adversary with access to the receive mode can block file upload for others. There is no way to block this attack in public mode due to the anonymity properties of the tor network.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| onionshare | onionshare | < 2.5 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | onionshare | 2.5-1 | — |
| Debian 13 | onionshare | 2.5-1 | — |
| Debian 12 | onionshare | 2.5-1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 22.04 LTS | onionshare | 2.2-3ubuntu0.1~esm1 | USN-7625-1 |
| Ubuntu Pro 20.04 LTS | onionshare | 2.2-1ubuntu0.1~esm1 | USN-7625-1 |
| Ubuntu Pro 18.04 LTS | onionshare | 0.9.2-1ubuntu0.1~esm1 | USN-7625-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 16.04 LTS | onionshare | 0.8.1-1ubuntu0.1~esm1 | USN-7625-1 |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | onionshare-cli | < 2.5 | 2.5 | GHSA-jh82-c5jw-pxpc |
Advisories 1
- USN-7625-1 onionshare vulnerabilities Ubuntu Security Notices (USN) · Jun 25, 2026