CVE-2020-15254

Name: CVE-2020-15254
Creator: NVD / NIST
Published: 2020-10-16T17:15:12.057+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

CRITICALCVSS 9.8/10EPSS 2.74%

Last modified Jun 17, 2026

CVE-2020-15254 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. 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. EPSS estimates a 2.74% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1

9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

2.74%

84.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Crossbeam Project	Crossbeam	< 0.4.4

References

https://github.com/RustSec/advisory-db/pull/425Patch, Third Party Advisory
https://github.com/crossbeam-rs/crossbeam/issues/539Exploit, Third Party Advisory
https://github.com/crossbeam-rs/crossbeam/pull/533Exploit, Patch, Third Party Advisory
https://github.com/crossbeam-rs/crossbeam/security/advisories/GHSA-v5m7-53cv-f3hxThird Party Advisory
https://github.com/RustSec/advisory-db/pull/425Patch, Third Party Advisory
https://github.com/crossbeam-rs/crossbeam/issues/539Exploit, Third Party Advisory
https://github.com/crossbeam-rs/crossbeam/pull/533Exploit, Patch, Third Party Advisory
https://github.com/crossbeam-rs/crossbeam/security/advisories/GHSA-v5m7-53cv-f3hxThird Party Advisory

Timeline

Published: Oct 16, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-15254?

How severe is CVE-2020-15254?

CVE-2020-15254 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 2.74% probability of exploitation in the next 30 days.

How do I fix CVE-2020-15254?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-15254?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST