CVE-2021-33363

Process-memory consumption via repeated encoding allocation

Published Sep 13, 2021 · Updated Aug 3, 2024

A memory leak in MP4Box's infe_box_read in GPAC 1.0.1 allows attackers to consume process memory through a crafted media file. When an infe box contains more than two strings, the function replaces content_encoding with a new allocation without freeing the prior buffer. A user must make MP4Box process the crafted file; extra strings consume heap memory, while the cited records do not establish direct disclosure of prior contents.

CVSS severity5.5
Medium
EPSS probability0.92%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

A memory leak in MP4Box's infe_box_read in GPAC 1.0.1 allows attackers to consume process memory through a crafted media file. When an infe box contains more than two strings, the function replaces content_encoding with a new allocation without freeing the prior buffer. A user must make MP4Box process the crafted file; extra strings consume heap memory, while the cited records do not establish direct disclosure of prior contents.

The record

CVE
CVE-2021-33363
Published
Sep 13, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-401
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 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?

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:P/I:N/A:N
5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N

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)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-401Missing Release of Memory after Effective Lifetime

Public exploit references

No public exploit references are available in this record.

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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