Malicious PDF — malware analysis report

Static analysis result for SHA-256 39b839ff65f9d471…

MALICIOUS

PDF

79.7 KB Created: 2021-05-28 21:48:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: e1c466ad54cba7a1168d15ef8692f5b9 SHA-1: ee0fa77ad30866ca9919ff6f644725671742ae69 SHA-256: 39b839ff65f9d471e684f435b7b12ad6a94f67feb41d41511ef8ff24fd4ac58c
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 0.9996

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://vilenefex.ru/123?utm_term=android+auto+wireless+subaru+ascent PDF link annotation
    • https://xomugewobi.weebly.com/uploads/1/3/0/8/130814749/vukuzunuw_fiwobamepasodim_webafakuf_tixejut.pdfIn PDF document text
    • https://xuzomavarek.weebly.com/uploads/1/3/1/3/131383242/df6a91102230.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4419849/normal_5ff270a0a80e3.pdfIn PDF document text
    • https://fowinojosusine.weebly.com/uploads/1/3/4/4/134495991/28546b08.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368745/normal_6044fe1362fad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4392453/normal_606b5b797955f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4490917/normal_6040abd5923af.pdfIn PDF document text
    • https://siralukamowifi.weebly.com/uploads/1/3/1/4/131407299/142044.pdfIn PDF document text
    • https://jukirabupunux.weebly.com/uploads/1/3/0/8/130874410/suvujuwus.pdfIn PDF document text
    • https://bidijewufamidu.weebly.com/uploads/1/3/5/3/135325384/4e37fe25adad.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4455670/normal_6023e6b4410c7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4389599/normal_6018beaeb4cda.pdfIn PDF document text
    • https://xigolomo.weebly.com/uploads/1/3/4/4/134483438/falob.pdfIn PDF document text
    • https://bafokaxaxex.weebly.com/uploads/1/3/4/8/134881351/2088455.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/65e2591f-1ed1-4a45-8c1e-683040207ccd/99735332739.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d86f8666-97f9-45ab-b04b-b2a66fe697a9/12124712778.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/97f48421-8c51-4b03-96f7-f83226b13215/wisoragobuxa.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3b3aac18-2f8b-4f47-99ef-cc2749111f79/how_to_review_math_for_the_gre.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/fc05cf94-cd2a-4147-9ba2-4e6d290faaa3/94583740965.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f61394eb-bb32-4f44-a01e-fe000df1dbd9/como_hacer_la_sangria_francesa_en_word_2019.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/af75210d-0e0b-407a-9765-196e61227f94/coding_basics_book.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_off0000eb6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB6A 5036 bytes
SHA-256: 1911acefb9a3debaae1fcf043554b3980d07715f53714753590cf00d3d218a64
font_01_sfnt_off0000fc9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC9D 10780 bytes
SHA-256: 8f346d7c16504d536d62cc1fddffe5a6ec34911fe473617ef003c297282bde14
font_02_sfnt_off000121a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121A2 4324 bytes
SHA-256: 1158d95dac44631f497756703988ba3645251422e7ff0015d3fca430225e7c3e