CVE-2021-35306Public exploitNetwork attack vector

Process crash via null sample-size pointer dereference

Published Aug 5, 2021 · Updated Aug 4, 2024

NULL pointer dereference in Bento4 1.6.0-636 and earlier allows attackers to crash mp42aac by processing a crafted MP4 file. AP4_StszAtom::WriteFields reads through a null pointer while cloning and writing a sample-size atom derived from the malformed input. Processing the attacker-supplied file requires user interaction, and the demonstrated consequence is limited to an mp42aac process crash.

CVSS severity6.5
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

NULL pointer dereference in Bento4 1.6.0-636 and earlier allows attackers to crash mp42aac by processing a crafted MP4 file. AP4_StszAtom::WriteFields reads through a null pointer while cloning and writing a sample-size atom derived from the malformed input. Processing the attacker-supplied file requires user interaction, and the demonstrated consequence is limited to an mp42aac process crash.

The record

CVE
CVE-2021-35306
Published
Aug 5, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1204.002
Attack vector
network
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 vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.5Canonical UbuntuCVSS: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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

T1204.002User Execution: Malicious File

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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