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CVE-2021-31162

31
FAUCET Score

CVE-2021-31162 is a critical double free vulnerability in the Rust standard library's Vec::from_iter function, affecting Rust versions prior to 1.52.0 and related Fedora projects. With a CVSS score of 9.8, it presents a severe risk due to its network-based attack vector, low attack complexity, and potential for complete compromise of confidentiality, integrity, and availability. While no active exploitation, public exploit code, or significant community discussion has been observed, the vulnerability's high FAUCET Risk Score of 81/100 warrants immediate patching.

Impacted Technologies

VendorProductVersion(s)CPE
>= 1.48.0, < 1.52.0CPE matchmatch criteria
cpe:2.3:a:rust-lang:rust:*:*:*:*:*:*:*:*
32CPE matchmatch criteria
cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*
33CPE matchmatch criteria
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
34CPE matchmatch criteria
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.1

9.8CRITICAL

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

Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
Exploitability Score
3.9
Impact Score
5.9
CvssVersion
3.1

Exploit Intelligence

EPSS Score
2.89%
Probability of exploitation in next 30 days
EPSS Percentile
85.5%
Percentile rank of EPSS score among Peer Group
As of 2026-07-28
Model: v2026.06.15
This CVE's current EPSS score of 0.0289 is in the 76th percentile among its peer group of 36,897 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.3 Bluesky, 0.3 Mastodon, and 2.4 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (8)

github_advisorypatch availablevia nvd_reference
View patch
microsoftpatch availablevia msrc
Product: 17941-16820Fixed in: 1.59.0-1
microsoftpatch availablevia msrc
Product: CBL Mariner 1.0 ARMFixed in: 1.59.0-1
microsoftpatch availablevia msrc
Product: cm1 rust 1.59.0-1 on CBL Mariner 1.0Fixed in: 1.59.0-1
microsoftpatch availablevia msrc
Product: CBL Mariner 1.0 x64Fixed in: 1.59.0-1
redhatpatch availablevia redhat_api
Product: Red Hat Developer ToolsFixed in: rust-toolset-1.52-0:1.52.1-1.el7_9
View patch
redhatpatch availablevia redhat_api
Product: Red Hat Developer ToolsFixed in: rust-toolset-1.52-rust-0:1.52.1-2.el7_9
View patch
redhatpatch availablevia redhat_api
Product: Red Hat Enterprise Linux 8Fixed in: rust-toolset:rhel8-8040020210603202531.2daa1a95
View patch

Vendor Advisories (3)

microsoft2023-Mar/CVE-2021-31162

CVE-2021-31162

Mar 14, 2023
microsoft2021-Apr/CVE-2021-31162Critical

In the standard library in Rust before 1.52.0 a double free can occur in the Vec::from_iter function if freeing the element panics.

Apr 13, 2021
redhatCVE-2021-31162Moderate

rust: double free in Vec::from_iter function if freeing the element panics

Mar 28, 2021

References

github.com / rust-lang/rust/issues/83618
ExploitThird Party Advisory
github.com / rust-lang/rust/pull/83629
PatchThird Party Advisory
github.com / rust-lang/rust/pull/84603
PatchThird Party Advisory
lists.fedoraproject.org / archives/list/package-announce%40lists.fedoraproject.org/message/CZ337CM4GFJLRDFVQCGC7J25V65JXOG5
lists.fedoraproject.org / archives/list/package-announce%40lists.fedoraproject.org/message/TFUO3URYCO73D2Q4WYJBWAMJWGGVXQO4
lists.fedoraproject.org / archives/list/package-announce%40lists.fedoraproject.org/message/VZG65GUW6Z2CYOQHF7T3TB5CZKIX6ZJE
security.gentoo.org / glsa/202210-09
Third Party Advisory