Malicious PDF — malware analysis report

Static analysis result for SHA-256 d3d41e7258f049b1…

MALICIOUS

PDF

86.8 KB Created: 2021-06-26 21:02:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: d9fd190ad5ed3e4dc57b19cdce4a9a99 SHA-1: f27affd042dc04eafb7d60537a775cf51676f0e1 SHA-256: d3d41e7258f049b153cb9fc2d87208331077d2a0e0ca57ce72eea3d2d60beb71
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links to compromised websites, identified by heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM'. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The embedded URLs point to various PDF files hosted on these compromised sites, suggesting a multi-stage attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 https://akproauto.com/nbloom/fckuploads/file/22324259087.pdf In PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160786e311dbcd---gezijujotiwulo.pdfIn PDF document text
    • http://luatsubienhoa.com/upload/ck/files/fepewakenanexagadibirigi.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160701bb854991---girujodavubudarel.pdfIn PDF document text
    • http://al-bandak.com/userfiles/file/80380747069.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/52d1c5da9635e8025ab7febb14c9a405/xozesubuwapidotofiz.pdfIn PDF document text
    • https://loskutova.site/wp-content/plugins/super-forms/uploads/php/files/99a51df04cecd5f1a69e7c030d5fbf5a/xegefalamogejudizobuzebo.pdfIn PDF document text
    • http://xperion.hu/wp-content/plugins/super-forms/uploads/php/files/6d804aab6d2200301ac3f8493c775fe3/37111742565.pdfIn PDF document text
    • http://devison-matras.com/upload/file/zonebivexujiponudibazek.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/446c60860a97f91945aabeb88571a114/57570774544.pdfIn PDF document text
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba5c69dd34f---71300794611.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/a2u8gmap0n1qkv9q2cvmsjg6m7/22648801154.pdfIn PDF document text
    • https://simplehome.ro/ckfinder/userfiles/files/bunob.pdfIn PDF document text
    • https://tlpnw.com/wp-content/plugins/super-forms/uploads/php/files/996f7b017e95a9bb3082054a152d9f7f/lipurefelemas.pdfIn PDF document text
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609b70be1ed12---tikejugivupenamipizos.pdfIn PDF document text
    • https://pharma-tools.eu/galeria/file/97257799315.pdfIn PDF document text
    • http://mu-rrrc.com/userfiles/file/bokuvefow.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/388758258c11ae2a94ef04e4f9e4925b/22310441832.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/srithdiqvfeudun3g1hbrksc01/kazajedoparulo.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/16075b902a56f9---delafisununar.pdfIn PDF document text
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f48424696c---varudolenibivetatam.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/01s4pa6v06r8vuv421vq43o4vi/wimuzalonabina.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9548ad60fd---lagefavebitamebukufuxav.pdfIn PDF document text
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160812775cda44---92810669358.pdfIn PDF document text
    • https://bahia-group.com/ckfinder/userfiles/files/90672491692.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=pipeline+cost+estimating+manualPDF 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_off0000efb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFB9 17328 bytes
SHA-256: 8ada65764363aeffea222128886a2c97165c305a73c77d560684ab6f67e27fd0
font_01_sfnt_off00011cda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CDA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000134f1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134F1 10720 bytes
SHA-256: b76249d366bcbf49295031dca0b8e3fb367bf1ab9f90fc62ce3e79c46bb5d0be