Malicious PDF — malware analysis report

Static analysis result for SHA-256 278e3238c97d41a2…

MALICIOUS

PDF

79.5 KB Created: 2021-04-08 07:05:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 7cfdfc976ed6472d6b8ffdaa435141f7 SHA-1: 913b1a468d4759dd68e882732f1800e943247505 SHA-256: 278e3238c97d41a2df5a85b179f44f3370e82df7fbbb34eb0e8d9753387443f0
186 Risk Score

Malware Insights

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

This PDF file contains a large number of external links, many of which point to disposable hosting services, indicating a link farm or SEO spam operation. The primary URL, 'https://mezovuduw.ru/strik?utm_term=guitar+exercises+for+speed+and+accuracy', suggests a lure related to musical exercises. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution through the link farm. No scripts were extracted, but the PDF structure itself is used to host the malicious links.

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://mezovuduw.ru/strik?utm_term=guitar+exercises+for+speed+and+accuracy PDF link annotation
    • https://fuzakeraza.weebly.com/uploads/1/3/4/8/134848422/sotakalajoj.pdfIn PDF document text
    • https://gidunixodon.weebly.com/uploads/1/3/5/3/135322071/8704704.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4380701/normal_6004f360a17d2.pdfIn PDF document text
    • https://neminijovasagig.weebly.com/uploads/1/3/4/6/134603544/fovonasevuzudos-gitodagojifafe-pezobex-wenagidukuk.pdfIn PDF document text
    • https://wegujelad.weebly.com/uploads/1/3/0/8/130813898/pasajomikolaviv-renuki-rufife-minimunixamalab.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485822/normal_601610ab01f4a.pdfIn PDF document text
    • https://rikelakejif.weebly.com/uploads/1/3/4/8/134885243/dabevudilogilej_wovimafudolixuw_kitedunetufip_bibumemajat.pdfIn PDF document text
    • https://sevenunoxesu.weebly.com/uploads/1/3/4/3/134341304/221e7e14c96306.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476765/normal_6025fa76ddc87.pdfIn PDF document text
    • https://nopiviwefimak.weebly.com/uploads/1/3/4/7/134708781/jovodirivegatax-dosofetuduwa-tageva-roxigozag.pdfIn PDF document text
    • https://pavufunipuz.weebly.com/uploads/1/3/4/2/134265556/3055380.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453334/normal_602686fb2d305.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4413362/normal_605d8be09f2b0.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://juxawewoguseku.epizy.com/evaluating_algebraic_expressions_worksheets.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/be9dbc0e-dd87-4be6-9535-a859239d46b2/situational_leadership_test_questions.pdfIn PDF document text
    • http://gumijodopivu.rf.gd/63205944740.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4f569e62-c58c-4984-b5d2-0f8f593c7c36/chamberlain_whisper_drive_parts.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cac215b1-2c0d-45c9-8336-b44efe07d167/63138790956.pdfIn PDF document text
    • http://vujiwexamofone.rf.gd/urbanismo_social_medellin.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b4454969-7628-4de7-a3d9-ce6b19b97e7d/juvoragojisamosewalanano.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_off0000fab0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAB0 5316 bytes
SHA-256: 63eaaf6350429e8514730a1777b8b67564b890e1ed8d2fd46672e6fb46062add
font_01_sfnt_off00010ce7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CE7 10344 bytes
SHA-256: 87c591ed66ee1aa1757a1e6262d205c0f9b49677a2792150fb277973df0687d1