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CVE-2020-15254 High

crossbeam-channel Undefined Behavior before v0.4.4

### Impact The affected version of this crate's 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. ### Patches This has been fixed in crossbeam-channel 0.4.4. We recommend users to upgrade to 0.4.4. ### References See https://github.com/crossbeam-rs/crossbeam/pull/533, https://github.com/crossbeam-rs/crossbeam/issues/539, and https://github.com/RustSec/advisory-db/pull/425 for more details. ### License This advisory is in the public domain.

Exploit probability 2.8%
Published August 25, 2021
Required by Not available
Last source change July 8, 2026

02 / AFFECTED SOFTWARE

Affected packages

Unknown Unknown

49 explicit affected versions

crates.io crossbeam-channel

1 explicit affected versions

crates.io crossbeam-channel
crates.io crossbeam-channel

03 / CONNECTIONS

Connected vulnerabilities

related OPENSUSE-SU-2024:14572-1

04 / EVIDENCE

Source records

Open Source Vulnerabilities CVE-2020-15254

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.

View original source
Open Source Vulnerabilities GHSA-v5m7-53cv-f3hx

### Impact The affected version of this crate's 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. ### Patches This has been fixed in crossbeam-channel 0.4.4. We recommend users to upgrade to 0.4.4. ### References See https://github.com/crossbeam-rs/crossbeam/pull/533, https://github.com/crossbeam-rs/crossbeam/issues/539, and https://github.com/RustSec/advisory-db/pull/425 for more details. ### License This advisory is in the public domain.

View original source
Open Source Vulnerabilities GHSA-m8h8-v6jh-c762

The affected version of this crate's 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.

View original source
Open Source Vulnerabilities RUSTSEC-2020-0052

The affected version of this crate's 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.

View original source

05 / REFERENCES

Further evidence