PT-2026-34748 · Swupdate · Swupdate

Vulncheck · Published 2026-04-23 · Updated 2026-04-24 · CVE-2026-28525

Positive Technologies (AI Summary)

CVSS v4.0

8.2

High

Base vector

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

Name of the Vulnerable Software and Affected Versions SWUpdate (affected versions not specified)

Description An integer underflow exists in the multipart upload parser within the mongoose multipart.c file. Unauthenticated attackers can cause a denial of service by sending a crafted HTTP POST request to the '/upload' endpoint with a malformed multipart boundary and controlled TCP stream timing. This triggers an integer underflow in the mg http multipart continue wait for chunk() function when the buffer length is within a specific range, leading to an out-of-bounds heap read that writes data beyond the allocated receive buffer to a local IPC socket.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Integer Underflow

Out of bounds Read

Weakness Enumeration

CWE-191

CWE-125

Related Identifiers

CVE-2026-28525

Affected Products

Swupdate

References · 9

• https://github.com/sbabic/swupdate/commit/beee2dc0feef1cfe84f1aa6fc980e104b2e47a74 · Patch
• https://ubuntu.com/security/CVE-2026-28525 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-28525 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-28525 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-28525 · Security Note
• https://security-tracker.debian.org/tracker/CVE-2026-28525 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2026-28525 · Security Note
• https://twitter.com/vuldb/status/2047549395688915415 · Twitter Post
• https://vulncheck.com/advisories/swupdate-integer-underflow-in-multipart-upload-parser · Note