How severe is CVE-2020-36440?

CVE-2020-36440 has a CVSS score of 8.1/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2020-36440?

CVE-2020-36440 affects the following packages: libsbc (crates.io). Ecosystems affected: crates.io.

How do I fix CVE-2020-36440?

Update libsbc to 0.1.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-36440 is resolved across your whole dependency graph.

How do I detect CVE-2020-36440 in my crates.io dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for libsbc. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate CVE-2020-36440 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against CVE-2020-36440?

O3 pinpoints whether CVE-2020-36440 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2020-36440 actively exploited in the wild?

No public exploit code has been indexed for CVE-2020-36440 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

When was CVE-2020-36440 published, and has it been updated?

CVE-2020-36440 was published on August 25, 2021 and was last updated on November 8, 2023. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🦀

🦀 crates.io

Not in CISA KEV

HIGH severity

CVE-2020-36440

HIGHFix: mvertescher/libsbc-rs@a34d6e1

CVE-2020-36440 is a high-severity (CVSS 8.1) remote code execution vulnerability in libsbc. O3 Security confirms whether CVE-2020-36440 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.

Data races in libsbc

Also known asRUSTSEC-2020-0120

Published

Aug 25, 2021

Updated

Nov 8, 2023

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 8, 2023 · OSV.dev, FIRST.org (EPSS)

Real-World Exposure

1 pkg affected

🦀libsbc

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects crates.io packages — download data is not available via public APIs for these ecosystems.

Description

Affected versions of this crate implements Send for Decoder<R> for any R: Read. This allows Decoder<R> to contain R: !Send and carry (move) it to another thread.

This can result in undefined behavior such as memory corruption from data race on R, or dropping R = MutexGuard<_> from a thread that didn't lock the mutex.

The flaw was corrected in commit a34d6e1 by adding trait bound R: Send to the Send impl for Decoder<R>.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🦀crates.io	`libsbc`	all versions	0.1.5

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for libsbc. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update libsbc to 0.1.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2020-36440 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2020-36440 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to CVE-2020-36440. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Affected versions of this crate implements `Send` for `Decoder<R>` for any `R: Read`. This allows `Decoder<R>` to contain `R: !Send` and carry (move) it to another thread. This can result in undefined behavior such as memory corruption from data race on `R`, or dropping `R = MutexGuard<_>` from a thread that didn't lock the mutex. The flaw was corrected in commit a34d6e1 by adding trait bound `R: Send` to the `Send` impl for `Decoder<R>`.

O3 Security · Impact-Aware SCA

Is CVE-2020-36440 in your dependencies?

O3 detects CVE-2020-36440 across crates.io dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works