CVE-2016-9604: kernel security
Vulnerability summary
CVE-2016-9604 is a medium (CVSS 4.4) vulnerability in kernel security. EPSS estimates a 0.27% chance of exploitation in the next 30 days, higher than 19.3% of scored vulnerabilities.
Not severe (CVSS 4.4, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 13 · Related 6Timeline
- 11-07-2018PublishedVulnerability first disclosed.
- 06-08-2024Last modifiedVulnerability information updated.
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.
CVSS metrics
5 scores · 4 sources · 2 versions- NVDNIST4.4MediumCVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N
- OSV · UbuntuEcosystem advisory · calculated4.4MediumCVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N
- OSV · DebianEcosystem advisory · calculated4.4MediumCVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N
EPSS trend
Probability
0.27%
Chance of exploitation in the next 30 days
Percentile
19%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.27% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-732Incorrect Permission Assignment for Critical ResourceThe product specifies permissions for a security-critical resource in a way that allows that resource to be read or modified by unintended actors.
- CWE-347Improper Verification of Cryptographic SignatureThe product does not verify, or incorrectly verifies, the cryptographic signature for data.
Affected systems
Known conditions: local access, administrative account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu21 products
- linux< 3.13.0-132.181 | < 4.4.0-79.100
- linux-aws< 4.4.0-1018.27
- linux-azureAll versions (No fix recorded)
- linux-azure-6.11All versions (No fix recorded)
- linux-azure-fdeAll versions (No fix recorded)
Debian1 product
- linux< 4.9.25-1
Kernel1 product
- securitykernel 4.11-rc8
Linux1 product
- linux_kernel≤ 4.11 | 4.11:rc1 | 4.11:rc2 | 4.11:rc3 | 4.11:rc4 | 4.11:rc5 | 4.11:rc6 | 4.11:rc7
4 vendors · 24 products
References
17 links- bugzilla.redhat.com/show_bug.cgi?id=CVE-2016-9604X Refsource CONFIRMIssue TrackingThird Party Advisory
- people.canonical.com/~ubuntu-security/cve/2016/CVE-2016-9604.htmlX Refsource CONFIRMThird Party Advisory
