Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6ae94a6bf4b41a9…

MALICIOUS

PDF

80.0 KB Created: 2021-05-24 22:53:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: efd91a42ecac54d86ec9a2d9cac990dc SHA-1: 596272c226a1d587364e8872d2296ecba73b6797 SHA-256: a6ae94a6bf4b41a92d0eeff1e12e00eae503847202fac191abf375641c481746
186 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to disposable hosting and employing UTM parameters, indicative of a link farm or SEO spam campaign. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are consistent with techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://pelibifir.ru/wb?keyword=micro%20expressions%20training%20tool%20free PDF link annotation
    • https://kunoloxudiruk.weebly.com/uploads/1/3/4/7/134767428/3556137.pdfIn PDF document text
    • https://jetetinabalu.weebly.com/uploads/1/3/2/6/132682142/d8bbdbd219ca.pdfIn PDF document text
    • https://buwulikifem.weebly.com/uploads/1/3/4/5/134583505/bazutowogagobipar.pdfIn PDF document text
    • https://zedusolurifi.weebly.com/uploads/1/3/3/9/133999882/40df1.pdfIn PDF document text
    • https://juvirafiwak.weebly.com/uploads/1/3/4/3/134307718/4363005.pdfIn PDF document text
    • https://loseseseveru.weebly.com/uploads/1/3/0/8/130813975/lananuden_bilegado.pdfIn PDF document text
    • https://dowawanezezezo.weebly.com/uploads/1/3/1/0/131070762/kofade.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4452372/normal_606c3399eaa95.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4381340/normal_60637dd89610e.pdfIn PDF document text
    • https://kusavavatixe.weebly.com/uploads/1/3/4/8/134878613/fajowosijevexa_xofejif_wewizof.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4457318/normal_603734d7212ec.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/a1c5f93e-d196-448d-9cd2-e9d7b793a24b/sanyo_tv_universal_remote_buy.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4d69c61e-1600-44c6-9aec-2811be9eba9e/lorozasiniravowafixu.pdfIn PDF document text
    • https://s3.amazonaws.com/resabomibogodaw/reading_skills_practice_test_3_answer_key.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a4600b74-ae22-483d-9d2a-5b83cca9fe5b/maximum_principal_stress_yield_criterion.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6d4f236e-bc66-4c41-a0ab-03229cc49199/8010186403.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7bfdfa9e-bbc1-4006-8de8-85237d68480e/is_uconnect_free_2019.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/95f00566-1e8a-4104-a669-ab63818307e1/voxixuradojekujaverobe.pdfIn PDF document text
    • https://s3.amazonaws.com/lanaladu/kiwelusuw.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/59799662-1d83-410c-a43e-7133c174c5bc/zifawususojug.pdfIn PDF document text
    • https://s3.amazonaws.com/tujeviwakirawu/wotukutobimizem.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6d7e6da0-89d2-47c0-aedd-72622bbddc1e/facebook_messenger_tech_support_phone_number.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/706ee02d-1f3d-4ee9-8b81-050e8999c375/gosigotepofa.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_off0000faed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAED 5256 bytes
SHA-256: f7a33f0fd247782776da49d1349f01a6681d6b79228c991e93a550e6684a0a4f
font_01_sfnt_off00010cf7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CF7 10992 bytes
SHA-256: c461cdc67ea3724d887d18a44063b0dbae3280d4b61566c05e979ff4f7221591