Malicious PDF — malware analysis report

Static analysis result for SHA-256 4fa4136341b3128e…

MALICIOUS

PDF

109.8 KB Created: 2021-07-06 08:04:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e4c4fd1d53b9a5131a2848763966db1d SHA-1: 08b4208de19fdb0d106fbf6d5699242c431ee660 SHA-256: 4fa4136341b3128e30ed37d2363182ca7c066e6c6b8192522872ded4f4ec6ff1
156 Risk Score

Malware Insights

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

The PDF contains numerous links to other PDF files hosted on compromised websites, indicating a link farm designed to distribute malicious content. ClamAV detected this file as 'Pdf.Phishing.Trojan', and ML classifiers also flagged it as malicious. The primary attack pattern involves directing users to potentially harmful external resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9666

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://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/2df086ca2b3d0184adc8e723f02b2736/zunolula.pdf
    • http://adamlegal.com/userfiles/file/85375435761.pdf
    • https://wpsqld.com.au/wp-content/plugins/super-forms/uploads/php/files/f35c96cc572929f688295081891035c1/8446487434.pdf
    • https://promocionesnma.com/wp-content/plugins/super-forms/uploads/php/files/44a766e01076d8dd67ea73c08d90cfa5/luxilunopi.pdf
    • https://otoform.com/upload/ckfinder/files/fubebowuditutafo.pdf
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b37097bdf9a---jogebiponasi.pdf
    • https://www.helpforbusymums.com/wp-content/plugins/super-forms/uploads/php/files/982a7a66b61b7fc98af8fff5a9297755/molazuwivokapakoxujano.pdf
    • https://fedico.ca/upload/editor/file/53309365339.pdf
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a9889e76ef5---13810373721.pdf
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/2hj5pqfk560tnbqrn5qdht5ca5/fugedi.pdf
    • https://www.andimoda.com/wp-content/plugins/super-forms/uploads/php/files/a2172c2072775773fc3e53ece2bd5d03/jebazewesemogigolilazi.pdf
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609de547719df---6049671731.pdf
    • http://kojeneckezbozi.eu/userfiles/file/sirubesegotazovelafowize.pdf
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/ic8o2r4s1ja3hmur1ugni9m042/nenumuvew.pdf
    • https://clubforeducation.com/FCKeditor/userfiles/file/motijufafavanusiguxavamu.pdf
    • http://assytekservizi.com/userfiles/files/50536302506.pdf
    • http://scoutpate.com/userfiles/file/46033027498.pdf
    • https://actioncoach.com.my/wp-content/plugins/formcraft/file-upload/server/content/files/160886c039f95a---mubesafed.pdf
    • https://postelezmasivu-ostrava.cz/ckfinder/userfiles/files/ruperagobofugolepapisoler.pdf
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099d0fed56e9---pefomir.pdf
    • http://cuatro-pr.org/sites/default/files/file/fonuvik.pdf
    • http://superfishinglewood.com/uploads/files/vakenegepipigur.pdf
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/828fac8e4b54defe3fdcc5be29d7745e/bawukukowipawekuzi.pdf
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/4c28904ek0oesl9quesqua89fa/vamaxafulizejawufobatalu.pdf
    • http://nicenpos.com/userData/board/file/74175092170.pdf
    • http://mesterek.net/tmp/jokabefikogati.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=polynomial+roots+example
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012fe1.bin
1c8cb79d14f53c3d1c0c26cd9f3b81ca7a2017a043408d48347b1243602ddd9d
pdf-font-stream PDF embedded font (sfnt) at offset 0x12FE1 10632 bytes
font_01_sfnt_off0001483b.bin
49eacb6428d6e222b65ae34c16f3cb4007f69f4508a0a005afe2ea66cbaf5616
pdf-font-stream PDF embedded font (sfnt) at offset 0x1483B 20032 bytes
font_02_sfnt_off00017c42.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x17C42 16792 bytes
font_03_sfnt_off00019453.bin
325c5f5cda05429ae92d15c23118ca1b8712e485108c584e1e30b0ff615913b7
pdf-font-stream PDF embedded font (sfnt) at offset 0x19453 16084 bytes