CVE-2018-1000168: Input Validation
If ALTSVC frame is received by libnghttp2 and it is larger than it can accept, the pointer field which points to ALTSVC frame payload is left NULL. Later libnghttp2 attempts to access another field through the pointer, and gets segmentation fault. The largest frame size libnghttp2 accept is by default 16384 bytes.
Receiving ALTSVC frame is disabled by default. Application has to enable it explicitly by calling nghttp2optionsetbuiltinrecvextensiontype(opt, NGHTTP2ALTSVC).
Transmission of ALTSVC is always enabled, and it does not cause this vulnerability. ALTSVC frame is expected to be sent by server, and received by client as defined in RFC 7838.
Affected versions: nghttp2 >= 1.10.0 and nghttp2 <= v1.31.0
Other sources
nghttp2 version >= 1.10.0 and nghttp2 <= v1.31.0 contains an Improper Input Validation CWE-20 vulnerability in ALTSVC frame handling that can result in segmentation fault leading to denial of service. This attack appears to be exploitable via network client. This vulnerability appears to have been fixed in >= 1.31.1.
Affected Software
Event History
Frequently Asked Questions
What is CVE-2018-1000168?
CVE-2018-1000168 is a vulnerability in nghttp2 version >= 1.10.0 and nghttp2 <= v1.31.0 that contains an Improper Input Validation CWE-20 vulnerability in ALTSVC frame handling.
How severe is CVE-2018-1000168?
CVE-2018-1000168 has a severity rating of 7.5 (high).
Which software versions are affected by CVE-2018-1000168?
nghttp2 version >= 1.10.0 and <= v1.31.0, Node.js versions 6.0.0 to 6.8.1, 8.4.0 to 8.17.0, and 9.0.0 to 9.11.2, as well as Debian Linux version 9.0 are affected by CVE-2018-1000168.
How can the CVE-2018-1000168 vulnerability be exploited?
The CVE-2018-1000168 vulnerability can be exploited through a network client.
How can I fix CVE-2018-1000168?
To fix CVE-2018-1000168, you should update your nghttp2 package to version 1.31.1.