CVE-2026-36499
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 · uneditedA missing upper-bound check in the udpif_set_threads() function of Open vSwitch v3.6.90 allows an attacker with OVSDB write access to request an excessive number of handler or revalidation threads. This can cause a denial of service (DoS) via resource exhaustion.
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 confidenceThe udpif_set_threads() function in Open vSwitch v3.6.90 lacks proper upper-bound validation on thread count parameters, allowing authenticated attackers with OVSDB write access to configure excessively high numbers of handler or revalidation threads, causing resource exhaustion and denial of service.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
CVSS 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
- Network
- Complexity
- Low
- Privileges
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/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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Identify Open vSwitch versionRun 'ovs-vsctl --version' or 'ovs-appctl --version' to determine the installed Open vSwitch versionAffected if Version is 3.6.90 or if the udpif_set_threads() function exists without upper-bound validation on thread counts
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Verify OVSDB write access exposureCheck if OVSDB interface is network-accessible or accessible to untrusted users; examine OVSDB server listening configuration with 'ovsdb-server/tcp:...' connectionsAffected if OVSDB accepts write connections from authenticated but untrusted users or is exposed to network attackers
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Inspect current thread configurationQuery current handler and revalidation thread settings via OVSDB or 'ovs-appctl -t udpif' interface if availableAffected if Thread count values can be modified to arbitrarily high numbers without validation failure
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Verify upper-bound enforcement on thread settingsAttempt to set an extremely high thread count via OVSDB client (e.g., ovsdb-client transact) and observe whether the request is accepted or rejectedAffected if The system accepts thread count values exceeding reasonable limits without returning an error
The environment is affected if Open vSwitch version 3.6.90 is running and OVSDB write access permits setting unlimited thread counts via udpif_set_threads().
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 dataImplement strict upper-bound validation on thread count parameters in udpif_set_threads() and enforce administrative limits on OVSDB-configurable thread counts to prevent resource exhaustion.
- Consultation2.0 h
- Implementation4.0 h
- Testing2.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $2,848.
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Free · runs locallyCheck whether your project pulls in CVE-2026-36499 — 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-2026-36499 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
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- Version or environment caveats, and links to real fixes
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