CVE-2025-29329

CriticalPublic PoC

Published: 12 January 2026

Published

12 January 2026

Modified

22 January 2026

KEV Added

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Patch

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CVSS Score 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Score 0.0200 83.9th percentile

Risk Priority 21 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-29329 is a critical-severity Classic Buffer Overflow (CWE-120) vulnerability in Sagemcom F\@St 3686 Firmware. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 16.1% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-16 (Memory Protection).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190). What defenders deploy: see the NIST 800-53 controls recommended below.

Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

SI-2 Flaw Remediation good match

prevent

Directly remediates the buffer overflow flaw in the ippprint service by requiring timely patching of the vulnerable firmware.

SI-10 Information Input Validation good match

prevent

Enforces validation of crafted HTTP requests to the ippprint service, preventing buffer overflows from malicious inputs.

SI-16 Memory Protection good match

prevent

Implements memory protections such as non-executable stacks and address space randomization to block arbitrary code execution from buffer overflows.

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access

Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.

attack.mitre.org →

Why these techniques?

Buffer overflow in public-facing ippprint service (IPP over HTTP) enables unauthenticated remote arbitrary code execution, directly facilitating T1190: Exploit Public-Facing Application.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

NVD Description

Buffer Overflow in the ippprint (Internet Printing Protocol) service in Sagemcom F@st 3686 MAGYAR_4.121.0 allows remote attacker to execute arbitrary code by sending a crafted HTTP request.

Deeper analysisAI

CVE-2025-29329 is a buffer overflow vulnerability, classified under CWE-120, affecting the ippprint service that implements the Internet Printing Protocol in Sagemcom F@st 3686 routers running firmware version MAGYAR_4.121.0. Published on 2026-01-12, the flaw enables a remote attacker to execute arbitrary code by sending a crafted HTTP request to the vulnerable service.

The vulnerability carries a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), marking it as critical. Any unauthenticated remote attacker with network access to the device can exploit it with low complexity and no user interaction required, achieving high-impact compromise of confidentiality, integrity, and availability through arbitrary code execution.

Vendor advisories and additional details are available at http://fst.com and http://sagemcom.com, while a proof-of-concept exploit is hosted at https://github.com/SilverS3c/Sagemcom-fast-3686-ippprint.