GHSA-pg9f-39pc-qf8g — crossbeam-channel
Fix: crossbeam-rs/crossbeam#1187GHSA-pg9f-39pc-qf8g is a CWE-415 vulnerability in crossbeam-channel. A fix is available for crossbeam-channel — see the affected versions and patch details below.
crossbeam-channel Vulnerable to Double Free on Drop
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for GHSA-pg9f-39pc-qf8g.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
crossbeam-channelReal-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
The internal Channel type's Drop method has a race
which could, in some circumstances, lead to a double-free.
This could result in memory corruption.
Quoting from the upstream description in merge request #1187:
The problem lies in the fact that
dicard_all_messagescontained two paths that could lead tohead.blockbeing read but only one of them would swap the value. This meant thatdicard_all_messagescould end up observing a non-null block pointer (and therefore attempting to free it) without settinghead.blockto null. This would then lead toChannel::dropmaking a second attempt at dropping the same pointer.
The bug was introduced while fixing a memory leak, in upstream MR #1084, first published in 0.5.12.
The fix is in upstream MR #1187 and has been published in 0.5.15
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🦀crates.io | crossbeam-channel | ≥ 0.5.12&&< 0.5.15 | 0.5.15cargo update -p crossbeam-channel --precise 0.5.15 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for crossbeam-channel, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update crossbeam-channel to 0.5.15 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-pg9f-39pc-qf8g 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-pg9f-39pc-qf8g can be triaged on real exposure rather than presence alone.
Tailored to GHSA-pg9f-39pc-qf8g. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-pg9f-39pc-qf8g in your dependencies?
O3 Security finds GHSA-pg9f-39pc-qf8g across crates.io dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.