Malicious PDF — malware analysis report

Static analysis result for SHA-256 953b2216bf98cfdc…

MALICIOUS

PDF

72.5 KB Created: 2021-06-01 14:40:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 79a4b1ea08e713ea7195525cb6db98a7 SHA-1: 944d155045c0b1ba226f0b4780485ee679cd46f0 SHA-256: 953b2216bf98cfdc8a9d3d697a203e07dc87c73645ddeca96e7020712a45d0c0
134 Risk Score

Malware Insights

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

The PDF contains multiple heuristics indicating malicious intent, including a high ML classifier score and ClamAV detection as a phishing trojan. It also features a link farm on disposable hosting, with one prominent URL pointing to 'infrive.ru'. While no scripts were extracted, the presence of external URIs and the 'SE_DOWNLOAD_BUTTON' heuristic suggest the document's primary purpose is to trick the user into navigating to a malicious site, likely for a second-stage download.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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=engineering+mechanics+dynamics+7th+edition+j.l+meriam+l.g.+kraige PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4458124/normal_6052a2bc64de5.pdfIn PDF document text
    • https://kagivosivozavex.weebly.com/uploads/1/3/4/7/134746508/55a0054bf8d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486983/normal_602e47a181541.pdfIn PDF document text
    • https://xizoputi.weebly.com/uploads/1/3/4/6/134679655/f716e1384931d.pdfIn PDF document text
    • https://rezomiwutamanap.weebly.com/uploads/1/3/4/3/134362688/a971c3d68c2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4387218/normal_60331a7fafa56.pdfIn PDF document text
    • https://wumotobabupe.weebly.com/uploads/1/3/0/7/130775865/poseradu.pdfIn PDF document text
    • https://fudexevanege.weebly.com/uploads/1/3/0/8/130814713/tagovuxijaxaror-vuvuvepuwapa-lagud.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://pamotekegopa.pbworks.com/w/file/fetch/144458895/84716386274.pdfIn PDF document text
    • http://wekibivu.pbworks.com/f/77081539006.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e05818e8-c918-4fca-9265-c00b95015e6d/64852421130.pdfIn PDF document text
    • http://togusan.pbworks.com/w/file/fetch/144427554/vamawukomejuzir.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/92898e00-e32a-416d-9c51-747d49e21cd7/fomubudoloj.pdfIn PDF document text
    • http://funuvutidip.pbworks.com/f/how_to_look_up_someones_rental_history.pdfIn PDF document text
    • http://dewubuk.pbworks.com/w/file/fetch/144422973/cuales_son_los_cereales_mas_saludables.pdfIn PDF document text
    • http://kolasotosexu.pbworks.com/f/tales_of_the_yawning_portal_maps.pdfIn PDF document text
    • http://wozixokumo.pbworks.com/f/dapabubajivipavewugasori.pdfIn PDF document text
    • http://sewafebi.pbworks.com/w/file/fetch/144426612/what_can_melchizedek_priesthood_holders_do.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7b04999c-445d-4514-82b6-88e192f347fb/depeche_mode_one_night_in_paris_setlist.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/07b33a72-fc78-4ca7-a81c-f53810e091d8/kawapimovam.pdfIn PDF document text
    • http://bawamotijeku.pbworks.com/f/vojolatufepenotatujoseme.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_off0000dc16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC16 5664 bytes
SHA-256: 4de36ac74c3ab66faa7b50d0c1a13971ad0caef4c8ebd0d16cd1ffa1494ad438
font_01_sfnt_off0000ef51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF51 10736 bytes
SHA-256: bfebdc6e384dc025865e0d954e916efcc6e40c8baa3e80711c277a1a0109e6c5