Description
Tornado before 6.6 contains a path traversal vulnerability in RequestHandler.static_url() and get_version() that allows attackers to hash files outside static_path using ../ sequences. Attackers controlling input passed to static_url() can obtain SHA-512 hashes of readable files to confirm their existence, or reference /dev/zero to block the event loop indefinitely.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| tornadoweb | tornado | < 6.6 | 6.6 |
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 | python-tornado | No fix yet | — |
| Debian 13 | python-tornado | No fix yet | — |
| Debian 12 | python-tornado | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | python-tornado | No fix yet | — |
| Ubuntu 26.04 LTS | python-tornado | No fix yet | — |
| Ubuntu 24.04 LTS | python-tornado | No fix yet | — |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 22.04 LTS | python-tornado | No fix yet | — |
| Ubuntu Pro 20.04 LTS | python-tornado | No fix yet | — |
| Ubuntu Pro 18.04 LTS | python-tornado | No fix yet | — |
| Ubuntu Pro 16.04 LTS | python-tornado | No fix yet | — |
Azure Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Azure Linux 3 | python-tornado | No fix yet | — |
References
- GitHub Security Advisory (GHSA-v8g8-cp5j-42fg) vendor-advisory
- VulnCheck Advisory: Tornado before 6.6 Path Traversal via static_url() Version Hashing third-party-advisory