CVE-2020-36469Network attack vector

Service interruption via unconditional Send and Sync

Published Aug 8, 2021 · Updated Aug 4, 2024

Memory-safety errors in the appendix crate 0.2.0 and earlier allow attackers to trigger data races or segmentation faults through unsafe use. Index<K, V> declares Send and Sync for every key and value type without requiring those traits, so non-thread-safe values can cross thread boundaries. The flaw is reachable only when a consuming application uses a non-Send or non-Sync type across threads; reference keys or values can also crash in crate code.

CVSS severity5.9
Medium
EPSS probability0.98%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory-safety errors in the appendix crate 0.2.0 and earlier allow attackers to trigger data races or segmentation faults through unsafe use. Index<K, V> declares Send and Sync for every key and value type without requiring those traits, so non-thread-safe values can cross thread boundaries. The flaw is reachable only when a consuming application uses a non-Send or non-Sync type across threads; reference keys or values can also crash in crate code.

The record

CVE
CVE-2020-36469
Published
Aug 8, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-362
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 8, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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

4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:N/A:P
5.9NIST NVDCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
5.9RustSecCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/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 exploitUnconfirmed

Weakness, pattern, technique

CWE-362Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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