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TI-2026-22785 Aliases CVE-2026-28525GHSA-hggv-rg65-qf4h

SWUpdate Integer Underflow in Multipart Upload Parser

Priority LOW 35CWE-125Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
High
Attack requirements
None
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-125 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00316 24th percentileScored 2026-11-07
Fix Fixed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
sbabicswupdateup to 2025.12—Patch availableCNA
  • swupdate Vendorsbabic Affected up to 2025.12 Fixed in — Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:swupdate:swupdate:*:*:*:*:*:*:*:*up to 2025.12VulnerableSwupdate
  • cpe:2.3:a:swupdate:swupdate:*:*:*:*:*:*:*:* Versions up to 2025.12 Vulnerable ·Swupdate

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-28525
  2. 2026-10-03 Alias added: GHSA-hggv-rg65-qf4h

References

Patch 1

  • TI-2025-27505 SWUpdate Untrusted Script Execution via Signed Update TOCTOU CVSS 4.0HIGH 7.3
  • TI-2026-71034 Improper certificate validation in SWUpdate lets forged updates install CVSS 4.0CRITICAL 9.2

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences