CVE-2021-28878

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.0% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2021-04-11 · updated 2026-06-17
Weakness: CWE-119

Description

In the standard library in Rust before 1.52.0, the Zip implementation calls __iterator_get_unchecked() more than once for the same index (under certain conditions) when next_back() and next() are used together. This bug could lead to a memory safety violation due to an unmet safety requirement for the TrustedRandomAccess trait.

Affected products

Fedoraproject Fedora: 32, 33, 34
rust-lang rust: before 1.52.0 — fixed in 1.52.0

How to fix

Upgrade to a fixed version: rust-lang rust 1.52.0. Check the vendor advisory for mitigations.

References

https://github.com/rust-lang/rust/issues/82291
https://github.com/rust-lang/rust/pull/82292
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CZ337CM4GFJLRDFVQCGC7J25V65JXOG5/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TFUO3URYCO73D2Q4WYJBWAMJWGGVXQO4/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VZG65GUW6Z2CYOQHF7T3TB5CZKIX6ZJE/
https://security.gentoo.org/glsa/202210-09
https://github.com/rust-lang/rust/issues/82291
https://github.com/rust-lang/rust/pull/82292
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CZ337CM4GFJLRDFVQCGC7J25V65JXOG5/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TFUO3URYCO73D2Q4WYJBWAMJWGGVXQO4/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/VZG65GUW6Z2CYOQHF7T3TB5CZKIX6ZJE/
https://security.gentoo.org/glsa/202210-09

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