CVE-2021-28951: fedoraproject fedora Improper Locking
Vulnerability summary
CVE-2021-28951 is a medium (CVSS 5.5) Improper Locking vulnerability in fedoraproject fedora. EPSS estimates a 0.28% chance of exploitation in the next 30 days, higher than 20.4% 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 3 · Related 1Timeline
- 20-03-2021PublishedVulnerability first disclosed.
- 03-08-2024Last modifiedVulnerability information updated.
Description
An issue was discovered in fs/io_uring.c in the Linux kernel through 5.11.8. It allows attackers to cause a denial of service (deadlock) because exit may be waiting to park a SQPOLL thread, but concurrently that SQPOLL thread is waiting for a signal to start, aka CID-3ebba796fa25.
CVSS metrics
4 scores · 3 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.28%
Chance of exploitation in the next 30 days
Percentile
20%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.28% 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 causeAffected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu23 products
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.3All versions (No fix recorded)
- linux-aws-5.8All versions (No fix recorded)
- linux-azureAll versions (No fix recorded)
- linux-azure-5.3All versions (No fix recorded)
Netapp5 products
Debian1 product
- linux< 5.10.26-1
Fedoraproject1 product
- fedoraEOL32 | 33 | 34
Linux1 product
- linux_kernel≤ 5.11.8
5 vendors · 31 products
