Malicious PDF — malware analysis report

Static analysis result for SHA-256 67c4fb41338fc75a…

MALICIOUS

PDF

81.3 KB Created: 2021-05-27 23:06:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: ab8d0e71b9191963e39904a315da8f54 SHA-1: ed0aed7d08b3e9cdfd8913f63350f4c315cea7c3 SHA-256: 67c4fb41338fc75aea8f92dcdd50d7a2dfd03bc40cf4051eab1eb77898faca25
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://zajinet.ru/strik?utm_term=how+to+cook+a+ham+joint+in+the+oven PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4485705/normal_6012261f66465.pdfIn PDF document text
    • https://namuxewanazojo.weebly.com/uploads/1/3/4/2/134266474/lefozerubomun_refupatoj.pdfIn PDF document text
    • https://funovupudejo.weebly.com/uploads/1/3/4/4/134473131/5449367.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447626/normal_5fd6fbe7c310e.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4372682/normal_5ff569724b79e.pdfIn PDF document text
    • https://wunobenera.weebly.com/uploads/1/3/4/8/134887230/7507747.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450630/normal_5fe6e894cb8a2.pdfIn PDF document text
    • https://gonokuxugun.weebly.com/uploads/1/3/1/6/131637302/9801467.pdfIn PDF document text
    • https://fotobuwab.weebly.com/uploads/1/3/4/3/134368258/xekefeke.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4381297/normal_5fccfccf2bdae.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4459337/normal_604691c52bad7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4392861/normal_6066f7c18769c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4407989/normal_60388d97af243.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/47123f93-b9eb-4aea-9796-a5076dba5918/bijeb.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7c0cae11-4357-4aab-815e-a3c29d12dd6b/zifadudomibazonefuzimalid.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3491b118-84d8-4780-83b8-01821dd1435a/how_do_you_reset_the_sunbeam_heating_pad.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f8ee1ad2-43ea-43d3-a48d-2b56fbaab6ea/what_are_the_symptoms_for_borderline_personality_disorder.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/10bc3045-52a7-46e5-89c2-6675eb39bc7a/55541863525.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a3632e7f-5a1d-4325-92c8-a2a22905abc4/the_outsider_synopsis_spoilers.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f164.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF164 4776 bytes
SHA-256: 35b178c37f4385857a8dfe49aa4fed159e189d28377aa12754512520268ef05d
font_01_sfnt_off00010189.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10189 11376 bytes
SHA-256: 9bce806067e893302a3959926259322694df5ebf0b8b95d61c29c685fb202572
font_02_sfnt_off00012823.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12823 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3