CVE-2021-24028Network attack vector

Crash and code execution via invalid union data

Published Apr 13, 2021 · Updated Aug 3, 2024

Invalid memory release in Facebook Thrift before 2021.02.22.00 allows remote attackers to crash or corrupt applications via malformed union data. The table-based C++ deserializer replaces an active union member without clearing it, then calls the wrong destructor if a duplicate replacement field is incomplete. Exposure requires an application to deserialize attacker-controlled duplicate union fields; consequences include a crash, memory corruption, or code execution.

CVSS severity9.8
Critical
EPSS probability1.75%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Invalid memory release in Facebook Thrift before 2021.02.22.00 allows remote attackers to crash or corrupt applications via malformed union data. The table-based C++ deserializer replaces an active union member without clearing it, then calls the wrong destructor if a duplicate replacement field is incomplete. Exposure requires an application to deserialize attacker-controlled duplicate union fields; consequences include a crash, memory corruption, or code execution.

The record

CVE
CVE-2021-24028
Published
Apr 13, 2021
Updated
Aug 3, 2024
Vendor
Meta Platforms, Inc.
Product
Facebook Thrift
Classifications
CWE-763
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 13, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <v2021.02.22.00

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Meta Platforms, Inc. · Facebook Thriftversion=unspecified <v2021.02.22.00

Published CVSS scores

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

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-763Release of Invalid Pointer or Reference

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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