Undefined Behavior in bounded Crossbeam channel
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution, Denial of service
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-119, CWE-401 and the CVSS impact.
Summary
Crossbeam is a set of tools for concurrent programming. In crossbeam-channel before version 0.4.4, the bounded channel incorrectly assumes that `Vec::from_iter` has allocated capacity that same as the number of iterator elements. `Vec::from_iter` does not actually guarantee that and may allocate extra memory. The destructor of the `bounded` channel reconstructs `Vec` from the raw pointer based on the incorrect assumes described above. This is unsound and causing deallocation with the incorrect capacity when `Vec::from_iter` has allocated different sizes with the number of iterator elements. This has been fixed in crossbeam-channel 0.4.4.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| crossbeam-rs | crossbeam | before 0.4.4 | 0.4.4 | Patch available | CNA |
| — | crossbeam-channel (crates.io) | 0.4.3 to before 0.4.4 | 0.4.4 | Patch available | GHSA-v5m7-53cv-f3hx |
- crossbeam Vendorcrossbeam-rs Affected before 0.4.4 Fixed in 0.4.4 Patch available CNA
- crossbeam-channel (crates.io) Vendor— Affected 0.4.3 to before 0.4.4 Fixed in 0.4.4 Patch available GHSA-v5m7-53cv-f3hx
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:crossbeam_project:crossbeam:*:*:*:*:*:*:*:* | before 0.4.4 | Vulnerable | crossbeam-rs |
- cpe:2.3:a:crossbeam_project:crossbeam:*:*:*:*:*:*:*:* Versions before 0.4.4 Vulnerable ·crossbeam-rs
Remediation
- Fix · CNA crossbeam (crossbeam-rs) Fixed in 0.4.4
- Fix · GHSA-v5m7-53cv-f3hx crossbeam-channel (crates.io) Fixed in 0.4.4 Advisory →
Vendor assessments
Red Hat
Red Hat rating: Important. Red Hat's page for this CVE →
Not affected: 3 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
Timeline
- 2026-10-02 Threatist record created from CVE-2020-15254
- 2026-10-03 Alias added: GHSA-v5m7-53cv-f3hx
References
Exploit 2
Advisory 2
More crossbeam-rs Crossbeam vulnerabilities
- TI-2022-07691 Improper Restriction of Operations within the Bounds of a Memory Buffer and Race Condition in crossbeam-utils CVSS 3.1HIGH 8.1
- TI-2021-12475 Data race in crossbeam-deque CVSS 3.1CRITICAL 9.8
- TI-2018-14958 An issue was discovered in the crossbeam crate before 0.4.1 for Rust. CVSS 3.0CRITICAL 9.8
Sources
- CVE-2020-15254 · CVE Program
- CVE-2020-15254 · NVD
- FIRST EPSS
- GHSA-v5m7-53cv-f3hx · GitHub Advisory Database · CC BY 4.0
- CVE-2020-15254 · Red Hat security data · CC BY 4.0
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