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PatchSiren cyber security CVE debrief

CVE-2016-10147 Linux CVE debrief

CVE-2016-10147 is a local denial-of-service issue in the Linux kernel’s crypto/mcryptd.c path. According to the CVE record, a local user can trigger a NULL pointer dereference and crash the system by using an AF_ALG socket with an incompatible algorithm, with mcryptd(md5) given as an example. The NVD record maps affected Linux kernel versions to those before 4.8.15 and assigns a medium severity score (CVSS 3.0 5.5), reflecting high availability impact but no direct confidentiality or integrity impact.

Vendor
Linux
Product
CVE-2016-10147
CVSS
MEDIUM 5.5
CISA KEV
Not listed in stored evidence
Original CVE published
2017-01-18
Original CVE updated
2026-05-13
Advisory published
2017-01-18
Advisory updated
2026-05-13

Who should care

Kernel and distro maintainers, platform teams running Linux systems that expose AF_ALG crypto interfaces, and operators of hosts where untrusted local code, containers, or multi-tenant workloads may run.

Technical summary

The vulnerability is described as a NULL pointer dereference in crypto/mcryptd.c when AF_ALG is used with an incompatible algorithm selection. The NVD weakness mapping is CWE-476 (NULL Pointer Dereference). Impact is limited to availability: a local attacker can cause a kernel crash or denial of service. The supplied record indicates the issue is fixed in Linux 4.8.15 and references a kernel commit and release changelog as remediation evidence.

Defensive priority

Medium. This is not a remote code execution issue, but it is a reliable local crash condition affecting kernel availability. Prioritize on systems that allow untrusted local execution, shared hosting, container hosts, and any fleet still running kernel versions earlier than 4.8.15.

Recommended defensive actions

  • Upgrade affected Linux kernels to 4.8.15 or a vendor backport that includes the fix.
  • Verify distro errata or kernel changelogs that reference the fix before scheduling remediation.
  • Review whether untrusted local users, containers, or sandboxed workloads have access to AF_ALG-related interfaces on exposed systems.
  • Treat repeated kernel crashes or NULL pointer dereference reports in crypto/mcryptd.c as a signal to confirm patch status immediately.
  • If upgrades must be delayed, reduce exposure by restricting who can execute local workloads on impacted hosts.

Evidence notes

This debrief is based only on the supplied CVE/NVD corpus and the referenced official or vendor-linked sources listed in the record. The CVE description states the crash condition and example algorithm misuse; the NVD metadata supplies the affected version boundary (before 4.8.15), CVSS vector, and CWE-476 mapping. No additional exploit details or unverified technical claims are included.

Official resources

The CVE record was published on 2017-01-18 and the supplied NVD record was last modified on 2026-05-13. The record indicates the issue was already addressed in Linux 4.8.15 and linked vendor/patch references.