FreeBSDOperating system
CVE-2026-49417
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedSecond, the audio buffer backing a mapping could be freed when the device was closed even though the mapping remained valid. The freed memory could then be reused elsewhere while still accessible through the stale mapping. The /dev/dsp device nodes are world-accessible by default. On a system with an audio device, either issue allows an unprivileged local user to read and write kernel memory, which can be used to escalate privileges, potentially gaining full control of the affected system. At a minimum, an attacker can crash the kernel, resulting in a Denial of Service (DoS).
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceA use-after-free vulnerability in the Linux OSS sound driver (/dev/dsp) allows the audio buffer backing a mapping to be freed when the device is closed while the mapping remains valid. The freed memory can then be reused elsewhere but remains accessible through the stale mapping, enabling unprivileged local users to read/write kernel memory.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data
FreeBSDOperating system
= 14.3= 14.4= 15.0CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Local
- Complexity
- High
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Check FreeBSD versionRun 'uname -r' or examine /etc/os-release to identify the installed FreeBSD versionAffected if Version is 14.3, 14.4, or 15.0
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Verify /dev/dsp device existsCheck if /dev/dsp or /dev/dsp* device nodes exist using 'ls -la /dev/dsp*'Affected if The /dev/dsp device node is present on the system
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Check device permissionsRun 'ls -la /dev/dsp*' to see ownership and permissions on the dsp deviceAffected if Device is accessible to unprivileged users (world-readable/writable or group allows unprivileged access)
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Verify OSS sound driver is loadedCheck if OSS driver is active via 'kldstat | grep -i oss' or test access to /dev/dsp by attempting to open itAffected if The OSS sound driver is loaded and /dev/dsp can be opened
System is affected if running FreeBSD 14.3, 14.4, or 15.0 with the /dev/dsp device present and accessible to unprivileged users while the OSS sound driver is active.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
From vendor dataRestrict access to /dev/dsp device nodes (chmod/chown) to prevent unprivileged access while awaiting an upstream kernel patch that properly synchronizes buffer lifecycle with active mappings.
Fix this in FreeBSD
Scoped from the published advisory
- Consultation6.0 h
- Implementation12.0 h
- Testing10.0 h
- Review / QA6.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $9,504.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2026-49417 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2026-49417 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
- No weaponised exploit code, or anything meant to cause harm
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