CVE-2020-11080 Information

Description

In nghttp2 before version 1.41.0 the overly large HTTP/2 SETTINGS frame payload causes denial of service. The proof of concept attack involves a malicious client constructing a SETTINGS frame with a length of 14400 bytes (2400 individual settings entries) over and over again. The attack causes the CPU to spike at 100. nghttp2 v1.41.0 fixes this vulnerability. There is a workaround to this vulnerability. Implement nghttp2_on_frame_recv_callback callback and if received frame is SETTINGS frame and the number of settings entries are large (e.g. 32) then drop the connection.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Reference

http://lists.opensuse.org/opensuse-security-announce/2020-06/msg00024.html https://github.com/nghttp2/nghttp2/commit/336a98feb0d56b9ac54e12736b18785c27f75090 https://github.com/nghttp2/nghttp2/commit/f8da73bd042f810f34d19f9eae02b46d870af394 https://github.com/nghttp2/nghttp2/security/advisories/GHSA-q5wr-xfw9-q7xr https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/AAC2AA36OTRHKSVM5OV7TTVB3CZIGEFL/ https://www.debian.org/security/2020/dsa-4696 https://www.oracle.com/security-alerts/cpujul2020.html https://www.oracle.com/security-alerts/cpuoct2020.html

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

NONE

Availability Impact

NONE

Base Score

HIGH

Base Severity

7.5