GHSA-w8gf-g2vq-j2f4 amphp/http-client Denial of Service via HTTP/2 CONTINUATION Frames
An attacker can cause a denial of service via unbounded memory consumption in the amphp/http-client library by sending crafted HTTP/2 CONTINUATION frames.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is GHSA-w8gf-g2vq-j2f4?
GHSA-w8gf-g2vq-j2f4 is a denial of service vulnerability in amphp/http-client, published on 3 Apr 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Early versions of amphp/http-client with HTTP/2 support (v4.0.0-rc10 to 4.0.0) will collect HTTP/2 CONTINUATION frames in an unbounded buffer and will not check the header size limit until it has received the END_HEADERS flag, resulting in an OOM crash. Later versions of amphp/http-client (v4.1.0-rc1 and up) depend on amphp/http for HTTP/2 processing and will therefore need an updated version of amphp/http, see GHSA-qjfw-cvjf-f4fm.
Acknowledgements
Thank you to Bartek Nowotarski for reporting the vulnerability.
Which versions are affected by GHSA-w8gf-g2vq-j2f4?
2 open source packages ship an affected version, including amphp/http-client.
| Package | Affected | Fixed in |
|---|---|---|
amphp/http-client Packagist | From 4.0.0-rc10 | 4.1.0-rc1 |
amphp/http-client Packagist | From 4.0.0-rc10 | 4.1.0-rc1 |
How do I fix GHSA-w8gf-g2vq-j2f4?
Upgrade amphp/http-client to 4.1.0-rc1 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is GHSA-w8gf-g2vq-j2f4 being exploited?
There is no known exploitation of GHSA-w8gf-g2vq-j2f4 in the wild and no public exploit code.