UBUNTU-CVE-2023-45288
An attacker may cause an HTTP/2 endpoint to read arbitrary amounts of header data by sending an excessive number of CONTINUATION frames. Maintaining HPACK state requires parsing and processing all HEADERS and CONTINUATION frames on a connection. When a request's headers exceed MaxHeaderBytes, no memory is allocated to store the excess headers, but they are still parsed. This permits an attacker to cause an HTTP/2 endpoint to read arbitrary amounts of header data, all associated with a request which is going to be rejected. These headers can include Huffman-encoded data which is significantly more expensive for the receiver to decode than for an attacker to send. The fix sets a limit on the amount of excess header frames we will process before closing a connection.
02 / AFFECTED SOFTWARE
Affected packages
1 explicit affected versions
2 explicit affected versions
10 explicit affected versions
8 explicit affected versions
2 explicit affected versions
5 explicit affected versions
10 explicit affected versions
9 explicit affected versions
2 explicit affected versions
2 explicit affected versions
2 explicit affected versions
5 explicit affected versions
7 explicit affected versions
2 explicit affected versions
2 explicit affected versions
4 explicit affected versions
1 explicit affected versions
4 explicit affected versions
2 explicit affected versions
2 explicit affected versions
3 explicit affected versions
4 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
An attacker may cause an HTTP/2 endpoint to read arbitrary amounts of header data by sending an excessive number of CONTINUATION frames. Maintaining HPACK state requires parsing and processing all HEADERS and CONTINUATION frames on a connection. When a request's headers exceed MaxHeaderBytes, no memory is allocated to store the excess headers, but they are still parsed. This permits an attacker to cause an HTTP/2 endpoint to read arbitrary amounts of header data, all associated with a request which is going to be rejected. These headers can include Huffman-encoded data which is significantly more expensive for the receiver to decode than for an attacker to send. The fix sets a limit on the amount of excess header frames we will process before closing a connection.
05 / REFERENCES
Further evidence
- https://go.dev/cl/576155
- https://groups.google.com/g/golang-announce/c/YgW0sx8mN3M
- https://kb.cert.org/vuls/id/421644
- https://pkg.go.dev/vuln/GO-2024-2687
- https://ubuntu.com/security/CVE-2023-45288
- https://ubuntu.com/security/notices/USN-6886-1
- https://ubuntu.com/security/notices/USN-7109-1
- https://ubuntu.com/security/notices/USN-7111-1
- https://www.cve.org/CVERecord?id=CVE-2023-45288