Skip to content
Noroxi
NVD / CVE Program· CNA Linux

CVE-2021-47096: ALSA: rawmidi - fix the uninitalized user_pversion

Noroxi assessment

Priority: Monitor (action score 16/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.21% (FIRST EPSS).
  • Someone with local access to the system can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: Linux Linux 39a8fc4971a00d22536aeb7d446ee4a97810611b, 5.15, b398fcbe4de1e1100867fdb6f447c6fbc8fe7085.
  • Mentioned 1 time in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Low priority for now. Upgrade to Linux Linux 39a8fc4971a00d22536aeb7d446ee4a97810611b, 5.15, b398fcbe4de1e1100867fdb6f447c6fbc8fe7085 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

In the Linux kernel, the following vulnerability has been resolved: ALSA: rawmidi - fix the uninitalized user_pversion The user_pversion was uninitialized for the user space file structure in the open function, because the file private structure use kmalloc for the allocation. The kernel ALSA sequencer code clears the file structure, so no additional fixes are required. BugLink: https://github.com/alsa-project/alsa-lib/issues/178

MediumCVSS 4.0 · v3.1—No exploit Fix available
Published
Mar 4, 2024
Updated
Jun 17, 2026
EPSS
0.2% · 11th percentile

Report tools

JSON

Action score

16

Monitor

Low priority for now.

CVSS
16 / 40 · 4.0 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.2%

CISA SSVC decision

Exploitation
none
Automatable
no
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2021-47096

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

One daily email digest (06:00 UTC); connect a webhook for KEV listings and weaponized exploits instantly.

Your free account also gets you

Running WordPress? Scan your site free with WP Lens

  • Stack alerts: add the products and versions you run, get the new CVEs that affect them
  • Uptime monitoring: 1 site, instant email when it goes down
  • Add your domain: subdomains and takeover risk scanned every week (1 domain)
  • 10 scans an hour on the security tools (3 a day without an account), an API key and MCP
  • All your scans in one panel: findings, what changed in the last scan, a report per domain or per client (PDF, share link)
All free tools

Sign up with email · Have an account? Sign in

Free account, no card. Unfollow any time.

Don't want an account? Get "Exploited this week" by email every MondayDon't want an account? RSS feed for linux records

Running WordPress? Scan your site free with WP Lens

Is your version affected? Check it

Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

We use this product, ask for help

Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
linuxlinux kernel

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • linux linux kernel5.15 and later · before 5.15.12
  • linux linux kernel5.16

Versions reported by the vendor

Affected version ranges reported by the assigning authority (Linux). Independent of NVD's CPE analysis and usually ahead of it.

  • Linux Linux

    • 12d50801497235956fb3760be8530f4e44e4ce67, 5.15affected
    • 09d23174402da0f10e98da2c61bb5ac8e7d79fdd and later · before b398fcbe4de1e1100867fdb6f447c6fbc8fe7085affected · git
    • 09d23174402da0f10e98da2c61bb5ac8e7d79fdd and later · before 39a8fc4971a00d22536aeb7d446ee4a97810611baffected · git
    • 5.14.10 and later · before 5.15affected · semver
    • before 5.15not affected · semver
    • 5.15.12 and later · up to and including 5.15.*not affected · semver
    • 5.16 and laternot affected · original_commit_for_fix

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
Debian:12linuxbefore 5.15.15-15.15.15-1
openSUSE:Leap 15.5dtb-aarch64before 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-64kbbefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-azurebefore 5.14.21-150500.33.48.15.14.21-150500.33.48.1
openSUSE:Leap 15.5kernel-debugbefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-defaultbefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-default-basebefore 5.14.21-150500.55.59.1.150500.6.25.75.14.21-150500.55.59.1.150500.6.25.7
openSUSE:Leap 15.5kernel-docsbefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-kvmsmallbefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-obs-buildbefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-obs-qabefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-rtbefore 5.14.21-150500.13.47.15.14.21-150500.13.47.1
openSUSE:Leap 15.5kernel-rt_debugbefore 5.14.21-150500.13.47.15.14.21-150500.13.47.1
openSUSE:Leap 15.5kernel-sourcebefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-source-azurebefore 5.14.21-150500.33.48.15.14.21-150500.33.48.1
openSUSE:Leap 15.5kernel-source-rtbefore 5.14.21-150500.13.47.15.14.21-150500.13.47.1
openSUSE:Leap 15.5kernel-symsbefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap 15.5kernel-syms-azurebefore 5.14.21-150500.33.48.15.14.21-150500.33.48.1
openSUSE:Leap 15.5kernel-syms-rtbefore 5.14.21-150500.13.47.15.14.21-150500.13.47.1
openSUSE:Leap 15.5kernel-zfcpdumpbefore 5.14.21-150500.55.59.15.14.21-150500.55.59.1
openSUSE:Leap Micro 5.3kernel-defaultbefore 5.14.21-150400.24.116.15.14.21-150400.24.116.1
openSUSE:Leap Micro 5.3kernel-default-basebefore 5.14.21-150400.24.116.1.150400.24.54.55.14.21-150400.24.116.1.150400.24.54.5
openSUSE:Leap Micro 5.3kernel-rtbefore 5.14.21-150400.15.76.15.14.21-150400.15.76.1
SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOSkernel-64kbbefore 5.14.21-150400.24.116.15.14.21-150400.24.116.1

+27

Same product

linux: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-31431crypto: algif_aead - Revert to operating out-of-placeKEV
    90Now
  • CVE-2022-0847A flaw was found in the way the "flags" member of the new pipe buffer structure was lacking proper initialization in copy_page_to_iter_pipe KEV
    89Now
  • CVE-2021-22555Heap Out-Of-Bounds Write in Netfilter IP6T_SO_SET_REPLACEKEV
    85Now

Published before and after this one in the same product

  • ← EarlierCVE-2021-47094Mar 4, 2024 · KVM: x86/mmu: Don't advance iterator after restart due to yielding
    31Monitor
  • ← EarlierCVE-2021-47095Mar 4, 2024 · ipmi: ssif: initialize ssif_info->client early
    22Monitor
  • Later →CVE-2021-47097Mar 4, 2024 · Input: elantech - fix stack out of bound access in elantech_change_report_id()
    28Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
Linux Linux39a8fc4971a00d22536aeb7d446ee4a97810611bVendor (CNA)
Linux Linux5.15Vendor (CNA)
Linux Linuxb398fcbe4de1e1100867fdb6f447c6fbc8fe7085Vendor (CNA)
debian:linux5.15.15-1 · Debian:12Package registry (OSV)
opensuse:dtb-aarch645.14.21-150500.55.59.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-64kb5.14.21-150500.55.59.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-debug5.14.21-150500.55.59.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-default5.14.21-150400.24.116.1 · openSUSE:Leap Micro 5.3Package registry (OSV)
opensuse:kernel-default-base5.14.21-150400.24.116.1.150400.24.54.5 · openSUSE:Leap Micro 5.3Package registry (OSV)
opensuse:kernel-docs5.14.21-150500.55.59.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-kvmsmall5.14.21-150500.55.59.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-obs-build5.14.21-150500.55.59.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-rt5.14.21-150400.15.76.1 · openSUSE:Leap Micro 5.3Package registry (OSV)
opensuse:kernel-rt_debug5.14.21-150500.13.47.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-source-rt5.14.21-150500.13.47.1 · openSUSE:Leap 15.5Package registry (OSV)
opensuse:kernel-syms-rt5.14.21-150500.13.47.1 · openSUSE:Leap 15.5Package registry (OSV)
suse:kernel-64kb5.14.21-150400.24.116.1 · SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOSPackage registry (OSV)
suse:kernel-default5.14.21-150400.24.116.1 · SUSE:Linux Enterprise Micro 5.3Package registry (OSV)
suse:kernel-default-base5.14.21-150400.24.116.1.150400.24.54.5 · SUSE:Linux Enterprise Micro 5.3Package registry (OSV)
suse:kernel-docs5.14.21-150400.24.116.1 · SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOSPackage registry (OSV)
suse:kernel-livepatch-SLE15-SP4_Update_251-150400.9.5.1 · SUSE:Linux Enterprise Live Patching 15 SP4Package registry (OSV)
suse:kernel-livepatch-SLE15-SP5-RT_Update_131-150500.11.3.1 · SUSE:Linux Enterprise Live Patching 15 SP5Package registry (OSV)
suse:kernel-obs-build5.14.21-150400.24.116.1 · SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOSPackage registry (OSV)
suse:kernel-rt5.14.21-150400.15.76.1 · SUSE:Linux Enterprise Micro 5.3Package registry (OSV)
suse:kernel-source5.14.21-150400.24.116.1 · SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOSPackage registry (OSV)
suse:kernel-source-rt5.14.21-150400.15.76.1 · SUSE:Linux Enterprise Micro 5.3Package registry (OSV)
suse:kernel-syms5.14.21-150400.24.116.1 · SUSE:Linux Enterprise High Performance Computing 15 SP4-ESPOSPackage registry (OSV)
suse:kernel-zfcpdump5.14.21-150400.24.116.1 · SUSE:Linux Enterprise Server 15 SP4-LTSSPackage registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2024-50302260 days apartHID: core: zero-initialize the report bufferKEV
    52Plan
  • CVE-2024-47685231 days apartnetfilter: nf_reject_ipv6: fix nf_reject_ip6_tcphdr_put()
    36Monitor
  • CVE-2024-2702258 days apartfork: defer linking file vma until vma is fully initialized
    31Monitor
  • CVE-2021-4755381 days apartsched/scs: Reset task stack state in bringup_cpu()
    31Monitor
  • CVE-2024-3689887 days apartgpiolib: cdev: fix uninitialised kfifo
    31Monitor
  • CVE-2024-50143248 days apartudf: fix uninit-value use in udf_get_fileshortad
    31Monitor

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

All national notices →

Technical details

Attack conditions

  • Someone with local access to the system can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
low · data can be read
Integrity
none
Availability
none
Attack vector
Local
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
Low
Integrity impact
None
Availability impact
None

Weakness class (CWE)

CWE-908 · Use of Uninitialized Resource

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (1 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records