Malicious PDF — malware analysis report

Static analysis result for SHA-256 83f44fe316af35e8…

MALICIOUS

PDF

71.2 KB Created: 2021-06-02 12:25:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 6c471e99ee6bffddf8d02db3d6f60fa0 SHA-1: 5d4425223f031f2c84a4ad9d7de0979a077b7849 SHA-256: 83f44fe316af35e8ed963fd80c9c1dfa0c6f5cd5ccfb49a72c42a3b2d81b4fb7
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by both a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. It contains a large number of external links, many pointing to disposable hosting, suggesting it's part of a link farm designed to drive traffic to potentially malicious sites. The document body, though heavily obfuscated, contains text related to downloading Android applications, which, combined with the link farm activity, points towards a phishing or malware distribution scheme.

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://wastran.ru/pbw?utm_term=auto+call+recorder+pro+apk+free+download+for+android PDF link annotation
    • https://xivitazekovobun.weebly.com/uploads/1/3/4/5/134596583/nuloxupedojuzun.pdfIn PDF document text
    • https://pivatebovuwize.weebly.com/uploads/1/3/0/7/130775292/7656780.pdfIn PDF document text
    • https://kikuwigew.weebly.com/uploads/1/3/1/4/131407235/denogodilakegivewi.pdfIn PDF document text
    • https://gesefamuredoxuk.weebly.com/uploads/1/3/4/6/134631359/207727e40080d.pdfIn PDF document text
    • https://ninobajoxakatud.weebly.com/uploads/1/3/4/7/134702009/71e849.pdfIn PDF document text
    • https://tubuzitobez.weebly.com/uploads/1/3/4/1/134108618/dulawosogi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/d57e733a-3859-4e32-b31b-405965f466b0/32737789697.pdfIn PDF document text
    • http://tisowowuduwe.pbworks.com/w/file/fetch/144424467/crucible_act_1_notes.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2c38d0fb-95ea-4bde-9f6d-4ae32e52c90f/homophones_worksheets_grade_1.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4a5f7e8a-c64d-46ad-942f-18df64470772/algebraic_equations_worksheet_5th_grade.pdfIn PDF document text
    • http://veniwusuj.pbworks.com/f/army_writer_failure_to_follow_instructions.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c00221b9-edbd-4158-80d3-d6d50aa6981a/when_worlds_collide_remake_2017.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/193aadd4-c3de-4683-bfe9-e3a0d01685e0/80092937098.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6760c1b0-448a-4305-a550-91cdef8afdc2/96310408365.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b84f4241-6d47-4974-a575-4256b5835200/fetawusuwotinutokigeg.pdfIn PDF document text
    • http://foxobekizax.pbworks.com/f/zindagi_ek_safar_hai_suhana_female_mp3_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3584f8fe-3c57-468a-88d4-59fe8e9368bd/94072550055.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1f8e65e1-6dcf-491b-910f-d503b7158d80/25457770434.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8beb94bb-b845-4f01-8c5d-8015bd53d2d5/18889698139.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/30e194e3-69fe-434a-8646-90628e0a6426/drift_max_world_mod_apk_unlimited_money.pdfIn 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_off0000d845.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD845 5116 bytes
SHA-256: dc391ec84bd08d4bf135221d1495a2463e4882f8880ffb7017634ed4afe42340
font_01_sfnt_off0000e9d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9D4 10848 bytes
SHA-256: 674bd6698fdb200b5387d660987f11a123f726f4b82015e11255eec41b31d7dd