sbabic swupdate up to 2025.12 mongoose_multipart.c mg_http_multipart_continue_wait_for_chunk integer underflow

CVSS Meta Temp Score
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CTI Interest Score
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5.2$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic was found in sbabic swupdate up to 2025.12. Affected is the function mg_http_multipart_continue_wait_for_chunk of the file mongoose_multipart.c. The manipulation results in integer underflow. This vulnerability is identified as CVE-2026-28525. The attack can be executed remotely. There is not any exploit available. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability classified as problematic has been found in sbabic swupdate up to 2025.12. Affected is the function mg_http_multipart_continue_wait_for_chunk of the file mongoose_multipart.c. The manipulation with an unknown input leads to a integer underflow vulnerability. CWE is classifying the issue as CWE-191. The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result. This is going to have an impact on availability. CVE summarizes:

SWUpdate contains an integer underflow vulnerability in the multipart upload parser in mongoose_multipart.c that allows unauthenticated attackers to cause a denial of service by sending a crafted HTTP POST request to /upload with a malformed multipart boundary and controlled TCP stream timing. Attackers can trigger an integer underflow in the mg_http_multipart_continue_wait_for_chunk() function when the buffer length falls within a specific range, causing an out-of-bounds heap read past the allocated receive buffer to a local IPC socket.

The weakness was released by Kazuma Matsumoto as beee2dc0feef1cfe84f1aa6fc980e104b2e47a74. The advisory is available at github.com. This vulnerability is traded as CVE-2026-28525 since 02/27/2026. The exploitability is told to be difficult. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Technical details are known, but there is no available exploit.

Applying the patch beee2dc0feef1cfe84f1aa6fc980e104b2e47a74 is able to eliminate this problem. The bugfix is ready for download at github.com.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-25307). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.2
VulDB Meta Temp Score: 5.2

VulDB Base Score: 3.7
VulDB Temp Score: 3.6
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.8
CNA Vector (VulnCheck): 🔒

CVSSv2info

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

Exploitinginfo

Class: Integer underflow
CWE: CWE-191 / CWE-189
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔒

Patch: beee2dc0feef1cfe84f1aa6fc980e104b2e47a74

Timelineinfo

02/27/2026 CVE reserved
04/23/2026 +54 days Advisory disclosed
04/23/2026 +0 days VulDB entry created
05/27/2026 +34 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: beee2dc0feef1cfe84f1aa6fc980e104b2e47a74
Researcher: Kazuma Matsumoto
Status: Confirmed

CVE: CVE-2026-28525 (🔒)
GCVE (CVE): GCVE-0-2026-28525
GCVE (VulDB): GCVE-100-359226
EUVD: 🔒

Entryinfo

Created: 04/23/2026 23:34
Updated: 05/27/2026 07:14
Changes: 04/23/2026 23:34 (79), 04/24/2026 05:02 (1), 05/27/2026 07:14 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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