CVE-2015-7550: linux linux_kernel
Vulnerability summary
CVE-2015-7550 is a medium (CVSS 5.5) vulnerability in linux linux_kernel. EPSS estimates a 0.41% chance of exploitation in the next 30 days, higher than 35.6% of scored vulnerabilities.
Not severe (CVSS 5.5, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 16 · Related 11Timeline
- 08-02-2016PublishedVulnerability first disclosed.
- 06-08-2024Last modifiedVulnerability information updated.
Description
The keyctl_read_key function in security/keys/keyctl.c in the Linux kernel before 4.3.4 does not properly use a semaphore, which allows local users to cause a denial of service (NULL pointer dereference and system crash) or possibly have unspecified other impact via a crafted application that leverages a race condition between keyctl_revoke and keyctl_read calls.
CVSS metrics
4 scores · 3 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.41%
Chance of exploitation in the next 30 days
Percentile
36%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.41% on 05-10-2026
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu21 products
- linux< 3.13.0-79.123
- linux-azureAll versions (No fix recorded)
- linux-azure-6.11All versions (No fix recorded)
- linux-azure-fdeAll versions (No fix recorded)
- linux-azure-fde-5.15All versions (No fix recorded)
Debian1 product
- linux< 4.3.3-3
Linux1 product
- linux_kernel≤ 4.3.3
3 vendors · 23 products
References
28 links- bugzilla.redhat.com/show_bug.cgi?id=1291197X Refsource CONFIRM
- github.com/torvalds/linux/commit/b4a1b4f5047e4f54e194681125c74c0aa64d637dX Refsource CONFIRM