Malicious PDF — malware analysis report

Static analysis result for SHA-256 1af8a55e3e8be544…

MALICIOUS

PDF

82.0 KB Created: 2021-06-08 06:24:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 6c998831cb7595f86b271f3dd87558ac SHA-1: ee4a739a4e8fb386cd2213218dcc899c6d17ebfb SHA-256: 1af8a55e3e8be54402ec73e9527a81beef2a75b622429e95e44b31376e231b8c
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 0.9991

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://infrive.ru/pbw?utm_term=vb.net+project+book+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4489730/normal_6045e3dc2dc57.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4449178/normal_5fd962c2d4c60.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413121/normal_60579c0540490.pdfIn PDF document text
    • https://vemusosafuz.weebly.com/uploads/1/3/1/3/131398108/427831.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446651/normal_60166292c5514.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4412908/normal_60396fa1e57a6.pdfIn PDF document text
    • https://xonujofepip.weebly.com/uploads/1/3/4/3/134385468/werogetos.pdfIn PDF document text
    • https://votujejigep.weebly.com/uploads/1/3/1/3/131380583/jujoxivewufinil-nerosawa-vuzananidibu-xuteb.pdfIn PDF document text
    • https://fukimeremunosav.weebly.com/uploads/1/3/1/3/131379236/17c5052.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453342/normal_5fd9de617163f.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4392439/normal_60066c53d3c79.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470826/normal_60bea4182e275.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376372/normal_601af1fbcef67.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4500882/normal_5ffc2b1c55138.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://munonoraze.pbworks.com/f/papas_pizzeria_unblocked_games_for_school.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fabd494f-0a27-4e4d-bdfd-485dbb8311c4/vajamikibedapevuvifewig.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f6913620-0562-403b-b506-5490979d49c2/how_do_i_change_my_polder_scale_to_grams.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/aac2db5f-27ff-4f25-8115-e1219b8c70d7/chicago_style_bibliography_single_or_double_spaced.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cf3c359f-372c-4277-9f3f-ac3764550bd4/consumo_de_drogas_tabaco_y_alcohol_en_los_adolescentes.pdfIn PDF document text
    • http://redelaw.pbworks.com/w/file/fetch/144652767/31879375121.pdfIn PDF document text
    • http://detomipipu.pbworks.com/w/file/fetch/144528399/notiteganeja.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8f3f6720-e3e4-4ed3-b62b-216d76fadc3c/46536861242.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a6537663-1f64-4caa-a8ed-f80ce661fe98/mewufelupepipoli.pdfIn PDF document text
    • http://zixereves.pbworks.com/w/file/fetch/144531843/loleratelufijuzoli.pdfIn PDF document text
    • http://nusuwoxub.pbworks.com/f/how_much_does_it_cost_to_open_a_kung_fu_tea_franchise.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_off000103b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103B8 5004 bytes
SHA-256: 0b6d1b0afee116ff5b95282ba90c3e6dde792c19f4f357f30a51978a063b31c4
font_01_sfnt_off000114dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114DC 10968 bytes
SHA-256: dc074474a3659fe94928834aff947d06972a13d6228fe8b6e57ca2de216bd801