Malicious PDF — malware analysis report

Static analysis result for SHA-256 e44880c050331e58…

MALICIOUS

PDF

71.2 KB Created: 2021-09-16 18:47:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 725fef8c68966f33d00a4920f6bf241b SHA-1: e8b5d7c7d30c4e61ea5c750525fddbf675bbd537 SHA-256: e44880c050331e582ad1a21946dfc8c27d72d661d41f2de4ee3c75df686c4b4b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. While no scripts were explicitly extracted, the PDF structure and heuristic firings suggest it is designed to exploit users by directing them to malicious external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://giaiphapthietke.vn/media/file/files/pidenuvubowawikanigironi.pdf In PDF document text
    • http://studiosantese.eu/userfiles/files/8514398054.pdfIn PDF document text
    • https://dpengineers.info/admin/userfiles/file/xexisisamerosoxerunusaj.pdfIn PDF document text
    • http://www.premiumimport.nl/ckfinder/userfiles/files/defufapipulopiremaxijo.pdfIn PDF document text
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139085964cd7---soroguwoj.pdfIn PDF document text
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/0c25d69a46d90f5fc499caf35942352b/zajoxizozudiritupu.pdfIn PDF document text
    • http://baovethanglongmb.com/upload/files/91423285652.pdfIn PDF document text
    • http://shqinze.net/admin/upimg/file///gububagujedo.pdfIn PDF document text
    • http://angerdress.store/ckfinder/userfiles/files/zenawe.pdfIn PDF document text
    • http://abriganature.centralcms.cloud/galeria/files/5072510124.pdfIn PDF document text
    • http://bangkokmagnetwire.com/ecodev_test/image_system/files/bilunovanurupabifunuviso.pdfIn PDF document text
    • http://cuacongtudongbinhduong.com/upload/files/ruzuvagurijikazugixejox.pdfIn PDF document text
    • http://bogaarchitetti.it/userfiles/files/63504951187.pdfIn PDF document text
    • http://jfhconsultancy.nl/userfiles/files/46884300854.pdfIn PDF document text
    • https://tenekedjieva.com/uploads/file/mulepofavelitetobagimoxav.pdfIn PDF document text
    • https://homestayhoian.vn/uploads/image/files/givazulobozowuxitil.pdfIn PDF document text
    • http://sake2metustin.com/uploads/files/pabotatedalawopekafegup.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/39e96e6ed37ae1e6e49abd24b087152d/lesuxiloletemi.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/161389e725672d---tegeni.pdfIn PDF document text
    • https://birotex.rs/images/files/95816803862.pdfIn PDF document text
    • http://bavlas.lt/ckfinder/userfiles/files/9824021016.pdfIn PDF document text
    • http://gyn-ordi.at/myPix/file/52497832504.pdfIn PDF document text
    • http://heatherjansch.com/ckfinder/userfiles/files/gizujavub.pdfIn PDF document text
    • http://socukorglutamatmentesfuszer.hu/ckfinder/userfiles/files/sidatituz.pdfIn PDF document text
    • https://peoplesmodelinternational.com/ckfinder/userfiles/files/56001672489.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=how+to+transfer+data+from+iphone+to+android+with+computerPDF 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_off0000b529.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB529 15816 bytes
SHA-256: d2a8e6908b62a667692cd2b1da73c3cfc62f4630cdf3c228b5869cdd8f4d02b3
font_01_sfnt_off0000dd83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD83 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f59a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF59A 11016 bytes
SHA-256: 9496177c8d4ff65315f38db931fd62a175d2d5b4af61b3c7063bb48540d0b564