Malicious PDF — malware analysis report

Static analysis result for SHA-256 ad1f511f5fd0da7d…

MALICIOUS

PDF

69.9 KB Created: 2021-05-28 01:24:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e961a1a011d40599fb4b53fe6b15cadc SHA-1: db64808cecc59ce87fda05b5c7e5d141153c88c4 SHA-256: ad1f511f5fd0da7d31edce12a896789fa659fdb4d8dd01ce8aa3c275814782de
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of external links, identified as a 'PDF_SEO_LINK_FARM' heuristic. While no scripts were explicitly extracted, the presence of external links and the 'ML_NYX_PDF_MALICIOUS' and 'CLAMAV_DETECTION' firings suggest malicious intent, likely to redirect users to malicious sites or download further payloads. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://cdn-cms.f-static.net/uploads/4488580/normal_602064b140164.pdf
    • https://static.s123-cdn-static.com/uploads/4489994/normal_5fe48c7c33b2b.pdf
    • https://guveroza.weebly.com/uploads/1/3/4/4/134484502/301883dd.pdf
    • https://zosupexaduj.weebly.com/uploads/1/3/0/7/130738593/6f6c46df463.pdf
    • https://cdn-cms.f-static.net/uploads/4486748/normal_606346cb30747.pdf
    • https://static.s123-cdn-static.com/uploads/4489598/normal_5fc8541d458ad.pdf
    • https://cdn-cms.f-static.net/uploads/4384150/normal_6021c4c2ad099.pdf
    • https://gemonozuwusub.weebly.com/uploads/1/3/4/1/134131657/d6f350458f.pdf
    • https://lafetewefovizav.weebly.com/uploads/1/3/4/3/134385578/1274919.pdf
    • https://cdn-cms.f-static.net/uploads/4453901/normal_6035f711b94f0.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://feedproxy.google.com/~r/wb/ENAH/~3/3IgsHNHpEfs/wb?keyword=2010%20chevrolet%20malibu%20lt%20w/1lt
    • https://uploads.strikinglycdn.com/files/10a8e91d-a017-45d7-8565-e36344ac5ca7/powermax_45_plasma_cutter_price.pdf
    • https://uploads.strikinglycdn.com/files/80567e49-9cd5-43dc-b97e-8f9e5967ee6c/92943207004.pdf
    • https://uploads.strikinglycdn.com/files/78b72674-2ad2-4f1f-9d22-480686c79f02/best_buy_las_vegas_locations.pdf
    • https://uploads.strikinglycdn.com/files/7e894de6-9e33-4cab-b6c8-32908b649b30/ashrae_handbook_refrigeration.pdf
    • https://uploads.strikinglycdn.com/files/3f1f5a16-fd9c-4a0f-a1f3-42570f9c24c1/where_is_the_choke_on_briggs_and_stratton_pressure_washer.pdf
    • https://uploads.strikinglycdn.com/files/d4b1ad45-19e7-4147-836b-5b15289f8c76/what_is_your_transcendental_meditation_mantra.pdf
    • https://uploads.strikinglycdn.com/files/bf3237f3-f17a-42a0-93e8-e891491fd9d2/how_to_open_old_sentry_safe_with_combination.pdf
    • https://uploads.strikinglycdn.com/files/4b1ba85c-4182-4734-bc8e-26b5317e3e69/javascript_quick_guide.pdf
    • https://uploads.strikinglycdn.com/files/913674bb-0e44-45c8-99e8-841a810533fa/16982065688.pdf
    • https://uploads.strikinglycdn.com/files/3033ee36-2da7-405f-a77e-ca069447da3e/autocad_software_download_for_mobile.pdf
    • https://uploads.strikinglycdn.com/files/2edee158-7533-4605-8af5-0e8a1c6e5e7d/what_is_the_nature_of_human_resource_management.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d49c.bin
70d4e15c44df73eb41279ecc9637039bac14f8dd9b307d1c03b721909f901092
pdf-font-stream PDF embedded font (sfnt) at offset 0xD49C 5420 bytes
font_01_sfnt_off0000e6ff.bin
3e25af0b5c6d449adb216514cb69361595b965dd25073cea60e076381e8450b5
pdf-font-stream PDF embedded font (sfnt) at offset 0xE6FF 10420 bytes