VOMIT (go/vomit) has received an external vulnerability report for the Linux kernel.
Advisory: CVE-2017-17806
Details: http://vomit.googleplex.com/advisory?id=CVE/CVE-2017-17806
CVSS severity score: 7.2/10.0
Description:
The HMAC implementation (crypto/hmac.c) in the Linux kernel before 4.14.8 does not validate that the underlying cryptographic hash algorithm is unkeyed, allowing a local attacker able to use the AF_ALG-based hash interface (CONFIG_CRYPTO_USER_API_HASH) and the SHA-3 hash algorithm (CONFIG_CRYPTO_SHA3) to cause a kernel stack buffer overflow by executing a crafted sequence of system calls that encounter a missing SHA-3 initialization.
This bug was filed by http://go/vomit
Please contact us at vomit-team@google.com if you need any assistance.
Comment 1 by groeck@chromium.org
, Jan 9 2018Owner: groeck@chromium.org
Status: WontFix (was: Untriaged)
Upstream commit af3ff8045bbf3 ("crypto: hmac - require that the underlying hash algorithm is unkeyed"). Fixed in chromeos-4.14 with stable release merge. Fixed in chromeos-4.4 with merge of v4.4.107. Per commit log, the problem only affects systems with SHA-3 support, and SHA-3 support must be enabled. chromeos-4.4 does not support SHA-3, meaning it and older kernels are not affected. Given that, no further action is necessary.