FedoraOperating system · Fedoraproject
CVE-2021-32810
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 · uneditedcrossbeam-deque is a package of work-stealing deques for building task schedulers when programming in Rust. In versions prior to 0.7.4 and 0.8.0, the result of the race condition is that one or more tasks in the worker queue can be popped twice instead of other tasks that are forgotten and never popped. If tasks are allocated on the heap, this can cause double free and a memory leak. If not, this still can cause a logical bug. Crates using `Stealer::steal`, `Stealer::steal_batch`, or `Stealer::steal_batch_and_pop` are affected by this issue. This has been fixed in crossbeam-deque 0.8.1 and 0.7.4.
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 race condition exists in crossbeam-deque versions prior to 0.7.4 and 0.8.0 where Stealer::steal, Stealer::steal_batch, and Stealer::steal_batch_and_pop can pop the same task multiple times while other tasks remain forgotten in the queue. This leads to double-free and memory leak vulnerabilities for heap-allocated tasks, or logical bugs for stack-allocated tasks.
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
FedoraOperating system
= 34< 0.7.4>= 0.8.0, < 0.8.1CVSS 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
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/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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Locate crossbeam-deque dependency versionSearch your project for Cargo.toml and Cargo.lock files. In Cargo.toml, look for 'crossbeam-deque' under [dependencies] or [dev-dependencies] and note the version specified. In Cargo.lock, find the [[package]] entry with name="crossbeam-deque" and read the version field.Affected if The version is less than 0.7.4, or greater than or equal to 0.8.0 but less than 0.8.1
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Identify Stealer method usage in source codeSearch your codebase for invocations of Stealer::steal, Stealer::steal_batch, or Stealer::steal_batch_and_pop. These are the three affected methods from the crossbeam::deque module.Affected if Any of these three Stealer methods are called in your code while using a vulnerable crossbeam-deque version
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Verify multi-threaded deque consumer patternExamine the code surrounding the Stealer method calls to determine if multiple threads or workers are consuming from the same deque concurrently using the affected methods.Affected if The Stealer methods are used in a multi-threaded context where race conditions on queue access could occur
You are affected if your project depends on crossbeam-deque version < 0.7.4 or >= 0.8.0 < 0.8.1 AND your code uses Stealer::steal, Stealer::steal_batch, or Stealer::steal_batch_and_pop in concurrent contexts.
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.
dbcve · scoped0.7.40.8.1
Upgrade crossbeam-deque to version 0.7.4, 0.8.1, or later via Cargo.toml dependency update, then thoroughly test all code paths using the affected Stealer methods to verify correct task processing behavior.
crossbeam-deque 0.7.4 or 0.8.1
- 1. Identify all Cargo.toml files in your project that depend on crossbeam-deque by running `cargo tree -p crossbeam-deque` or checking your Cargo.lock
- 2. Update the crossbeam-deque dependency in Cargo.toml to version 0.7.4 or 0.8.1 (e.g., `crossbeam-deque = "0.7.4"` or `crossbeam-deque = "0.8.1"`)
- 3. Run `cargo update crossbeam-deque` to update the lock file
- 4. Run `cargo build` or `cargo test` to verify the update compiles and tests pass
- 5. If using Fedora 34, ensure the system-level crossbeam packages are also updated via `sudo dnf update`
Generated from the published advisory — verify against the referenced sources before acting.
Fix this in Fedora
Scoped from the published advisory
- Consultation1.0 h
- Implementation1.0 h
- Testing4.0 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 $2,144.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-32810 — 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 sources- github.com
- lists.fedoraproject.org
- lists.fedoraproject.org
- lists.fedoraproject.org
- lists.fedoraproject.org
- lists.fedoraproject.org
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- lists.fedoraproject.org
- lists.fedoraproject.org
- lists.fedoraproject.org
- lists.fedoraproject.org
- lists.fedoraproject.org
- lists.fedoraproject.org
- lists.fedoraproject.org
- lists.fedoraproject.org
- nvd.nist.gov
Practitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-32810 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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