CVE-2021-36584Public exploit

Process crash via out-of-bounds UTF-16 probe

Published Aug 5, 2021 · Updated Aug 4, 2024

Out-of-bounds read in GPAC MP4Box 1.0.1 allows context-dependent attackers to crash the process via a crafted media file. During RTP hinting of timed text, gp_rtp_builder_do_tx3g tests data[2] and data[3] for a UTF-16 byte-order mark even when the sample buffer ends after two bytes. Triggering the fault requires MP4Box to process an attacker-supplied file with the -hint path, and AddressSanitizer shows an abort that interrupts only the MP4Box process.

CVSS severity5.5
Medium
EPSS probability0.76%
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 read in GPAC MP4Box 1.0.1 allows context-dependent attackers to crash the process via a crafted media file. During RTP hinting of timed text, gp_rtp_builder_do_tx3g tests data[2] and data[3] for a UTF-16 byte-order mark even when the sample buffer ends after two bytes. Triggering the fault requires MP4Box to process an attacker-supplied file with the -hint path, and AddressSanitizer shows an abort that interrupts only the MP4Box process.

The record

CVE
CVE-2021-36584
Published
Aug 5, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787, T1203
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 5, 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 vectorlocal
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
5.5NIST NVDCVSS:3.1/AV:L/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

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

Weakness, pattern, technique

CWE-787Out-of-bounds Write
T1203Exploitation for Client Execution

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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