Malicious PDF — malware analysis report

Static analysis result for SHA-256 efeb457477d846eb…

MALICIOUS

PDF

86.3 KB Created: 2021-09-18 15:46:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: d412c4e4fc65dbbaf21e0feab51e9d2a SHA-1: 4b94d57eb03cf3788cf8c30be93c374f5a55c0d2 SHA-256: efeb457477d846eb313b7f3e848dcc438f6f62d945c373017615bd43cc4e83ef
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics as malicious, including a ML classifier and ClamAV. It contains numerous links, many pointing to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The presence of external URIs and the overall structure suggest an attempt to distribute malicious content or phish for information.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://casaledellasignora.it/userfiles/files/vemodofid.pdf In PDF document text
    • http://agataklimowska.pl/userfiles/file/kagijojumegigibawejenid.pdfIn PDF document text
    • http://2446665a.ru/ckfinder/userfiles/files/zakexozeboxodifu.pdfIn PDF document text
    • http://tranhdaquydep.vn/upload/files/mobaz.pdfIn PDF document text
    • http://soudurelauziere.com/upload/editor/file/30824871411.pdfIn PDF document text
    • http://chinhsuasolieu.com/media/files/28087875010.pdfIn PDF document text
    • https://autopits-directo.migrupoq.com/ckfinder/userfiles/files/polasiwikowewivu.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/55c0b1a950c05e805e26888b90c355ec/55907597792.pdfIn PDF document text
    • http://home-hj.com/up_photo/file/duxuluduvomosok.pdfIn PDF document text
    • http://drivingschool-brno.eu/files/vipireradunamijurokox.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/16140bb0c96caa---butikusobefa.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/033adeea1b826c37fc4c62efc58c1212/lifisanalujoxemune.pdfIn PDF document text
    • http://andreuma.madteam.net/ckfinder/userfiles/files/xetuwejomobezaw.pdfIn PDF document text
    • https://rinducm1.com/contents/files/dofubenosidazatuposafa.pdfIn PDF document text
    • http://tafgambiatours.com/userfiles/file/namob.pdfIn PDF document text
    • http://pro-customer.de/userfiles/file/28592229437.pdfIn PDF document text
    • http://kanizsakran.hu/userfiles/file/gomuvufiv.pdfIn PDF document text
    • http://praguynakorn.com/praguynakorn/picture/datapro/files/joposanutit.pdfIn PDF document text
    • http://flairpens.ru/uploads/files/varakageba.pdfIn PDF document text
    • https://irastuff.com/admin/ckfinder/uploads/files/vejolitom.pdfIn PDF document text
    • https://franchise-vietnam.com/app/webroot/img/files/nenoxaralewemujuselator.pdfIn PDF document text
    • http://giprozdraw.ru/ckfinder/userfiles/files/biguwepuguvuwimugakiw.pdfIn PDF document text
    • https://semot.com/Store/userfiles/file/devirizipivasejodilor.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=all+things+fall+apart+book+pdfPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ebf0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBF0 18132 bytes
SHA-256: 6ab8fec0fe7f6c0f0acc42fb5f871948e974e85146fc6577f0cb6c43b121828d
font_01_sfnt_off00011b00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B00 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013317.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13317 10860 bytes
SHA-256: e6b98059ee8774d16ebf7e39e97b4faeb76c172e1c9c8747e20da72d06650c40