CVE-2021-34340Public exploitNetwork attack vector

Denial of service via unchecked register index

Published Mar 7, 2022 · Updated Aug 4, 2024

Out-of-bounds buffer access in LibMing Ming 0.4.8 allows attackers to crash swftophp by supplying a crafted SWF file. The decompileINCR_DECR function in util/decompile.c fails to validate an index before accessing the regs array during SWF action decompilation. Processing the file with swftophp is required; the demonstrated consequence is a segmentation fault and process termination, not code execution.

CVSS severity6.5
Medium
EPSS probability0.90%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds buffer access in LibMing Ming 0.4.8 allows attackers to crash swftophp by supplying a crafted SWF file. The decompileINCR_DECR function in util/decompile.c fails to validate an index before accessing the regs array during SWF action decompilation. Processing the file with swftophp is required; the demonstrated consequence is a segmentation fault and process termination, not code execution.

The record

CVE
CVE-2021-34340
Published
Mar 7, 2022
Updated
Aug 4, 2024
Vendor
Ming Development Team
Product
Ming
Classifications
CWE-787, CWE-125
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 7, 2022CVE 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?

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

  1. Affected versionversion=Ming 0.4.8

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Ming Development Team · Mingversion=Ming 0.4.8

Published CVSS scores

4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:N/A:P
6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/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 exploitPublished

Weakness, pattern, technique

CWE-787Out-of-bounds Write
CWE-125Out-of-bounds Read

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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