Malicious PDF — malware analysis report

Static analysis result for SHA-256 373b5bd2755d77e7…

MALICIOUS

PDF

82.5 KB Created: 2021-04-08 09:58:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: daef30d52426992576824a61bbb04c66 SHA-1: 109411df6a76faa14f070ebd89315893cebe6fa1 SHA-256: 373b5bd2755d77e70febab9b4632894a5466b8f8e887060a00919a1324c04df6
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://ponafet.ru/wix?keyword=population+distribution+worksheet+key PDF link annotation
    • http://voirly.xyz/wojowueeo3m.pdfIn PDF document text
    • http://lunesygets.xyz/80110858388vjma2.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://0633afab-057d-4448-85e1-ac1a97571725.filesusr.com/ugd/66920c_5dcbab3d0d8a47dcb07a80e0ac54a73c.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/ed295f9d-a745-4502-aa11-fef0e495a249/nuremevofuzafogemudof.pdfIn PDF document text
    • https://be9ca920-c372-4566-b00d-544f92814f3b.filesusr.com/ugd/f0c5a9_a605283d5f624b648a4e0c05e027a0ae.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/cc3c2236-42bf-42ee-a2ac-6ba3b1868b6a/the_tyranny_of_merit_ted_talk.pdfIn PDF document text
    • https://s3.amazonaws.com/kozibowisenatu/wilopudokev.pdfIn PDF document text
    • http://bapaxofobawob.rf.gd/86399475792.pdfIn PDF document text
    • https://s3.amazonaws.com/pexodugosa/54487971767.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e621b02f-7ebb-4d96-8a04-8f295a90d499/7648581183.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1350592c-e42d-43ea-afa6-6edcee3630c9/dedepodas.pdfIn PDF document text
    • https://s3.amazonaws.com/zedudo/mivuwisuxuv.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7a830f50-19c5-4dda-b588-eddb33ae8af7/66687570988.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/629a429d-82d6-46b6-8148-fded9a019960/tafibifixesaruviwaverim.pdfIn PDF document text
    • https://d1ced4a1-fa29-4c66-b583-77209f32159a.filesusr.com/ugd/c88d8b_e5c3691e95274650a1349d2729431b4e.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/dazovosugev/porque_me_da_mareo_al_levantarme.pdfIn PDF document text
    • http://zelixaxiki.rf.gd/recirculating_aquaculture_system.pdfIn PDF document text
    • http://fixuwebevu.epizy.com/79006247712.pdfIn PDF document text
    • http://vagawujososoje.epizy.com/33114319224.pdfIn PDF document text
    • https://1c019786-7048-4615-837a-ae53f087c4ae.filesusr.com/ugd/8b4172_85810079269a4ea4870cb55733389b4e.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/dc6e828e-358b-4c61-a518-b90a57c675b7/waxuwafawizijumadolizo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/90a72dbd-30f4-4ef7-9c61-16f7a140a599/why_is_deterrence_better_than_punishment.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_off00010351.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10351 5444 bytes
SHA-256: 35daba785c57f0ccd5a66550b711f8277511a4106631aace350ce3d236a06442
font_01_sfnt_off000115da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115DA 11336 bytes
SHA-256: 0c0e7a40c06886013f5e5fc20b6032a96a7229a404d47cf441b38f6d73136d34