undici vulnerable to Denial of Service via unhandled error on excessive content-encodings
Affected releases · undici
- 8.x8.0.0 – 8.12.1Fixed in 8.12.2
- 7.x7.18.0 – 7.30.0Fixed in 7.30.1
- 6.x6.23.0 – 6.29.0Fixed in 6.29.1
On 8.x, the newest line:
npm install undici@8.12.2Affected
8.0.0 – 8.12.1
22 releases
Fixed
8.12.2 – 8.12.3
2 releases, latest
Not affected
7.0.0 – 7.17.0
22 releases
Affected
7.18.0 – 7.30.0
28 releases
Fixed
7.30.1
1 release
Not affected
6.0.0 – 6.22.0
47 releases
Affected
6.23.0 – 6.29.0
9 releases
Fixed
6.29.1
1 release
Is your project affected?
Paste your package.json, or type the range you declare for undici. It is read in your browser and sent nowhere.
What happens
Impact
undici's fetch() crashes the Node.js process when a malicious server returns a response with more than five content codings and closes the connection before sending the body. undici rejects such responses (a content-encoding limit), but it created the internal response stream before that check and returned without attaching an error listener or aborting the request. The early close then surfaces a content-length mismatch on that orphaned internal stream, which Node.js treats as an unhandled error and terminates the process. A remote, unauthenticated server can trigger this with a single response, even when the application correctly catches the fetch() rejection. undici 6.x, 7.x, and 8.x are affected.
Patches
Upgrade to 6.29.1, 7.30.1, or 8.12.2. undici now validates the content-encoding chain before creating the internal body stream and aborts the response when the limit is exceeded, so no error can surface on an orphaned stream.
Workarounds
None.