CVE-2017-17806: Buffer Overflow
Last updated 4 July 2026
Other sources
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 AFALG-based hash interface (CONFIGCRYPTOUSERAPIHASH) and the SHA-3 hash algorithm (CONFIGCRYPTOSHA3) to cause a kernel stack buffer overflow by executing a crafted sequence of system calls that encounter a missing SHA-3 initialization.
— Launchpad
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
redhat/kernelto a version that resolves this vulnerability.Fixed in 4.14.8 - Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 5.10.223-1Fixed in 5.10.262-1Fixed in 6.1.176-1Fixed in 6.1.180-1Fixed in 6.12.94-1Fixed in 6.12.101-1Fixed in 7.1.7-1Fixed in 7.1.8-1 - Upgrade
Upgrade
linux kernelto a version that resolves this vulnerability.Fixed in 4.14.8Patch af3ff8045bbf3e32f1a448542e73abb4c8ceb6f1 - Compensating control
Ensure CONFIG_CRYPTO_USER_API_HASH is disabled and CONFIG_CRYPTO_SHA3 is not enabled on affected systems to prevent use of the AF_ALG-based hash interface and the SHA-3 hash algorithm as described for kernels before 4.14.8.
Event History
Frequently Asked Questions
What is the severity of CVE-2017-17806?
CVE-2017-17806 is a high-severity vulnerability due to improper validation in the HMAC implementation of the Linux kernel.
How do I fix CVE-2017-17806?
To fix CVE-2017-17806, upgrade to Linux kernel version 4.14.8 or later.
Which versions of Linux are affected by CVE-2017-17806?
CVE-2017-17806 affects Linux kernel versions prior to 4.14.8, including multiple versions within the range of 3.2 to 4.14.7.
Can CVE-2017-17806 be exploited remotely?
No, CVE-2017-17806 requires local access for exploitation due to its nature of attacking the HMAC implementation.
What systems should I prioritize for CVE-2017-17806 patching?
Systems running Linux kernels prior to version 4.14.8, especially those in sensitive environments, should be prioritized for patching against CVE-2017-17806.