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UnicycleApplication · Unicycle Project

CVE-2020-36436

HIGH · 8.1 CVSS v3.1 Published 2021-08-08
Fix available
A fix is available. Upgrade to 0.7.1 or later.
See remediation →
90/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

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 · unedited
An issue was discovered in the unicycle crate before 0.7.1 for Rust. PinSlab<T> and Unordered<T, S> do not have bounds on their Send and Sync traits.

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 confidence

The unicycle crate versions before 0.7.1 have PinSlab<T> and Unordered<T, S> types that incorrectly implement Send and Sync trait bounds. These types can be safely Send/Sync only when their type parameter T satisfies those traits, but the implementations were unconditionally implementing Send and Sync without proper bounds, potentially allowing data races when non-Send/Sync types are used with these containers.

MitigationUpgrade the unicycle crate to version 0.7.1 or later which adds proper Send/Sync trait bounds to PinSlab<T> and Unordered<T, S>. Review existing code to ensure no unsafe assumptions about thread safety were made.

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
UnicycleApplication
Affected:< 0.7.1

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
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 checks

Work through these to decide whether this CVE applies to you.

  1. Locate the unicycle crate in your project
    Search your Cargo.lock file for the 'name = "unicycle"' entry and read the version field, or run 'cargo tree -p unicycle' to see the version
    Affected if the version listed is less than 0.7.1 or no version is found (unicycle is not a direct dependency)
  2. Identify usage of PinSlab in your code
    Search your source files for 'PinSlab' imports or usage patterns like 'PinSlab::<T>::new()' or 'use unicycle::PinSlab'
    Affected if PinSlab is imported or instantiated anywhere in your codebase
  3. Identify usage of Unordered in your code
    Search your source files for 'Unordered' imports or usage patterns like 'Unordered::<T, S>::new()' or 'use unicycle::Unordered'
    Affected if Unordered is imported or instantiated anywhere in your codebase
  4. Check the type parameter T used with PinSlab or Unordered
    Review each usage of PinSlab<T> or Unordered<T, S> and identify what concrete type replaces T. Determine if that type implements Send and/or Sync (by checking its trait implementations or documentation)
    Affected if the type parameter T is a custom type that does NOT implement Send or does NOT implement Sync, and you are using a vulnerable unicycle version

You are affected if your project depends on unicycle crate version less than 0.7.1 AND uses PinSlab<T> or Unordered<T, S> with a type T that does not implement Send or does not implement Sync, allowing potentially unsafe cross-thread data access.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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.

dbcve · scoped
Upgrade available Upgrade to 0.7.1 or later
Fixed in 0.7.1
Interim mitigation

Upgrade the unicycle crate to version 0.7.1 or later which adds proper Send/Sync trait bounds to PinSlab<T> and Unordered<T, S>. Review existing code to ensure no unsafe assumptions about thread safety were made.

Recommended fix High confidence

unicycle version 0.7.1

  1. Locate your Cargo.toml file that declares the unicycle dependency
  2. Update the unicycle version constraint to ">=0.7.1" (e.g., unicycle = "0.7.1" or unicycle = ">=0.7.1")
  3. Run "cargo update unicycle" to fetch the patched version
  4. Run "cargo build" or "cargo check" to verify compilation succeeds with the new Send/Sync trait bounds
  5. If compilation fails due to new trait bound requirements, address any type constraints in your code that rely on the missing bounds
Caveat The new Send+Sync bounds are a strengthening of safety guarantees; code that previously compiled may fail if it implements PinSlab<T> or Unordered<T, S> with T that is not Send+Sync

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Unicycle Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA2.0 h
11.0 hours of engineering $1,930
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2020-36436 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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