CVE-2021-30455Public exploitNetwork attack vector

Process memory corruption via panic-unsafe map cloning

Published Apr 7, 2021 · Updated Aug 3, 2024

Double free in the id-map crate 0.2.1 and earlier allows attackers to corrupt memory when cloning a map whose value clone panics. IdMap::clone_from drops existing values and replaces its ID set before cloning replacements, so a panic leaves old slots marked live and drops them again. The vulnerable path requires a stored value's Clone implementation to panic; the resulting double free can crash or corrupt the consuming process.

CVSS severity9.8
Critical
EPSS probability1.10%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Double free in the id-map crate 0.2.1 and earlier allows attackers to corrupt memory when cloning a map whose value clone panics. IdMap::clone_from drops existing values and replaces its ID set before cloning replacements, so a panic leaves old slots marked live and drops them again. The vulnerable path requires a stored value's Clone implementation to panic; the resulting double free can crash or corrupt the consuming process.

The record

CVE
CVE-2021-30455
Published
Apr 7, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-415
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 7, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-415Double Free

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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