Malicious PDF — malware analysis report

Static analysis result for SHA-256 4bf1abc63a0d62df…

MALICIOUS

PDF

80.1 KB Created: 2021-03-17 08:40:09 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: e0c9b015e3c4ea21f6e5e8480bc3ce5d SHA-1: 976fbe7d2816bef450e31dbd4537075a6659a0de SHA-256: 4bf1abc63a0d62dff0322d78bc5d4bf0c6aa18bebc731f7eec7565b0b67ccb4b
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or SEO spam operation. The document body, though heavily obfuscated, appears to be related to 'checklist for autism spectrum disorder', likely a lure to disguise the malicious nature of the links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://vilenefex.ru/award?keyword=checklist+for+autism+spectrum+disorder+casd+pdf PDF link annotation
    • http://epaytds.xyz/best_thermostat_no_c_wiredyhyt.pdfIn PDF document text
    • https://cdn.sqhk.co/dewufidabo/hfij3ic/filter_sort_song_ringtone_download.pdfIn PDF document text
    • https://cdn.sqhk.co/movijomo/Bhhdwhe/horse_jumping_games_download.pdfIn PDF document text
    • http://xtreme-sport.ru/31207649170vdzh9.pdfIn PDF document text
    • https://cdn.sqhk.co/pulizojiwim/5Jgeifa/46570825489.pdfIn PDF document text
    • http://tuzirawejaw.mypressonline.com/clinical_anesthesia_8th_edition.pdfIn PDF document text
    • https://cdn.sqhk.co/garoresolif/mjbCgha/titan_quest_anniversary_edition_atlantis_walkthrough.pdfIn PDF document text
    • https://cdn.sqhk.co/dojidavos/Zjggehi/world_history_chapter_27_quizlet.pdfIn PDF document text
    • https://cdn.sqhk.co/muligumixe/gdau1ji/67357666264.pdfIn PDF document text
    • http://cmb-societe.com/2501868177344qzv.pdfIn PDF document text
    • http://tortomsk.ru/clackamas_county_courthouse_forms7h9kw.pdfIn PDF document text
    • http://sevoxotedeki.medianewsonline.com/88601231838.pdfIn PDF document text
    • http://miromawetibikew.mywebcommunity.org/traduction_anglais_franais_google.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://53002a68-e35f-4167-ac88-1ab9777d7e72.filesusr.com/ugd/f5bc2a_adaa432254564007b56aa124f92d526f.pdf?index=trueIn PDF document text
    • https://d427386d-3434-45d9-8802-370857a594f4.filesusr.com/ugd/accd1f_6ba29f0281144c0599d447aa53ae3a52.pdf?index=trueIn PDF document text
    • https://c6de0af5-2a4c-46da-924c-839bccb102c6.filesusr.com/ugd/5f1f0f_1a735c347e2d4ba0a33023530d173eaf.pdf?index=trueIn PDF document text
    • http://gitodake.myartsonline.com/bakri_palan_marathi.pdfIn PDF document text
    • https://1cdd1dcb-54a5-4750-95ad-c4cce9a68cd1.filesusr.com/ugd/1e32c2_0fcf05e01646402ca70b875aac6cc8fe.pdf?index=trueIn PDF document text
    • https://8569cc17-8b2a-4187-ace0-95b0550b99f0.filesusr.com/ugd/d6eede_ebf7de90ef5f49f6a6fc34e03c8d86d6.pdf?index=trueIn PDF document text
    • https://4590046d-f0a9-4171-b8a0-56ff8c1fe63c.filesusr.com/ugd/0bfb20_8b322ae83a994fc2ba36d18f708d52ac.pdf?index=trueIn PDF document text
    • https://d397443b-80d0-4e74-967c-4ce830ee3754.filesusr.com/ugd/0a76f0_ebf0af4e4d9846af9a34a5d10dff7cfe.pdf?index=trueIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000faaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAAF 5364 bytes
SHA-256: 8a694386065a05f64f79416181cab84462bad3aceb2c029896e79aa845f30182
font_01_sfnt_off00010cc0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CC0 11292 bytes
SHA-256: 4ed80c72bef60470c2b69526e0111d255e99d29c89a716932ec58e76987e29a7