GPAC MP4Box 2.4 isomedia/stbl_write.c stbl_AddSize heap-based overflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.2$0-$5k2.71

Summaryinfo

A vulnerability was found in GPAC MP4Box 2.4. It has been classified as problematic. This affects the function stbl_AddSize of the file isomedia/stbl_write.c. This manipulation causes heap-based overflow. The identification of this vulnerability is CVE-2025-55640. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability classified as problematic was found in GPAC MP4Box 2.4. Affected by this vulnerability is the function stbl_AddSize of the file isomedia/stbl_write.c. The manipulation with an unknown input leads to a heap-based overflow vulnerability. The CWE definition for the vulnerability is CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). As an impact it is known to affect availability. The summary by CVE is:

A heap buffer overflow in the stbl_AddSize function (isomedia/stbl_write.c) of GPAC MP4Box v2.4 allows attackers to cause a Denial of Service (DoS) via supplying a crafted MP4 file.

The advisory is shared at github.com. This vulnerability is known as CVE-2025-55640 since 08/13/2025. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 10/16/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.2

VulDB Base Score: 4.3
VulDB Temp Score: 4.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

08/13/2025 CVE reserved
10/16/2026 +429 days Advisory disclosed
10/16/2026 +0 days VulDB entry created
10/16/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: github.com
Status: Not defined

CVE: CVE-2025-55640 (🔒)
GCVE (CVE): GCVE-0-2025-55640
GCVE (VulDB): GCVE-100-421489

Entryinfo

Created: 10/16/2026 21:00
Changes: 10/16/2026 21:00 (55)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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