Async CoapApplication · Async Coap Project
CVE-2020-36444
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 · uneditedAn issue was discovered in the async-coap crate through 2020-12-08 for Rust. Send and Sync are implemented for ArcGuard<RC, T> without trait bounds on RC.
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 · moderate confidenceThe async-coap crate implements Send and Sync traits for ArcGuard<RC, T> without requiring trait bounds on the RC (resource controller) type parameter. This violates Rust's concurrency safety guarantees, potentially allowing data races when ArcGuard instances are shared across thread boundaries if RC does not itself implement Send and Sync.
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
Async CoapApplication
<= 2020-12-08CVSS 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
- High
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:H/PR:N/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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Identify async-coap dependencySearch your Cargo.lock or Cargo.toml files for the async-coap crate and note its versionAffected if The async-coap version is 2020-12-08 or earlier, or the version is unspecified and was downloaded before the patch date
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Locate ArcGuard usage in codeSearch source files for instances of ArcGuard type (e.g., grep 'ArcGuard<' or review crate documentation)Affected if ArcGuard is used anywhere in the codebase, as the unsafe Send+Sync implementations are on this type regardless of usage context
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Inspect cross-thread ArcGuard sharingSearch for code that passes ArcGuard values between threads via spawn, thread::spawn, or async executors that may move values across thread boundariesAffected if ArcGuard is shared across thread boundaries (e.g., moved into spawned threads or passed to concurrent async tasks on different executors)
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Check resource controller type boundsReview the RC (resource controller) type used with ArcGuard and check if it explicitly implements Send and Sync traitsAffected if The RC type parameter does NOT implement Send and Sync, creating potential for data races
You are affected if async-coap <= 2020-12-08 is in use AND ArcGuard instances with non-Send+Sync resource controllers are shared across thread boundaries.
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 dataAudit code for cross-thread usage of ArcGuard and upgrade to a patched version of async-coap once available, adding Send+Sync bounds on RC if manually backporting the fix.
Fix this in Async Coap
Scoped from the published advisory
- Consultation2.0 h
- Implementation2.0 h
- Testing3.0 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 $2,512.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2020-36444 — 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-2020-36444 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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- Version or environment caveats, and links to real fixes
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