How severe is CVE-2016-9604?

CVE-2016-9604 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2016-9604 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-9604?

CVE-2016-9604 primarily affects Linux Linux Kernel. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2016-9604?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2016-9604 published?

CVE-2016-9604 was published on 2018-07-11 and last updated on 2026-06-17.

CVE-2016-9604

CVE-2016-9604 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 4.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-347.

Key facts

Severity: Medium (CVSS 3.x base score 4.4)
CVSS v2: 2.1
EPSS exploit prediction: 0% (17th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-347
Affected product: Linux Linux Kernel
Published: 2018-07-11
Last modified: 2026-06-17

Description

It was discovered in the Linux kernel before 4.11-rc8 that root can gain direct access to an internal keyring, such as '.dns_resolver' in RHEL-7 or '.builtin_trusted_keys' upstream, by joining it as its session keyring. This allows root to bypass module signature verification by adding a new public key of its own devising to the keyring.

Frequently asked questions

What is CVE-2016-9604?: It was discovered in the Linux kernel before 4.11-rc8 that root can gain direct access to an internal keyring, such as '.dns_resolver' in RHEL-7 or '.builtin_trusted_keys' upstream, by joining it as its session keyring. This allows root to bypass module signature verification by adding a new public key of its own devising to the keyring.
How severe is CVE-2016-9604?: CVE-2016-9604 has a CVSS 3.x base score of 4.4, rated medium severity. It is exploitable over local access with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2016-9604 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-9604?: CVE-2016-9604 primarily affects Linux Linux Kernel. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-9604?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2016-9604 published?: CVE-2016-9604 was published on 2018-07-11 and last updated on 2026-06-17.

References

Affected products (8)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:4.11:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:4.11:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:4.11:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:4.11:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:4.11:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:4.11:rc6:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:4.11:rc7:*:*:*:*:*:*

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