CVE-2026-28525

HIGH EPSS 23.3%
Published Apr 23, 20262mo ago · Modified Jun 17, 20262w ago
8.2 CVSS 4.0
High
Find Similar
Published Apr 23, 2026 2mo ago
Last Modified Jun 17, 2026 2w ago

Description

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.

CVSS Details

Base Score
8.2
Exploitability
—
Impact
—
Vector string
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity High
Privileges Required None
User Interaction None
Scope X

Threat Intelligence

EPSS Exploit Probability
23.3% percentile
Exploit & Patch Status
No Known Exploit
Patch Available

Weaknesses 2

CWE-125 Out-of-bounds Read Memory Safety
CWE-191

Affected Products 1

VendorProductVersionRange
swupdateswupdate* ≤2025.12

References 2

  • github.com https://github.com/sbabic/swupdate/commit/beee2dc0feef1cfe84f1aa6fc980e104b2e47a74
    Patch
  • vulncheck.com https://www.vulncheck.com/advisories/swupdate-integer-underflow-in-multipart-upload-parser
    Third Party Advisory

Remediation

  • github.com https://github.com/sbabic/swupdate/commit/beee2dc0feef1cfe84f1aa6fc980e104b2e47a74
    Patch