Malicious PDF — malware analysis report

Static analysis result for SHA-256 3f6033a7cccf7d3b…

MALICIOUS

PDF

119.7 KB Created: 2021-06-30 21:54:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3ab88c8937b23666801e20eda5bd20ec SHA-1: ef9c8dcc384534b37b14a3d267a78475ee200b18 SHA-256: 3f6033a7cccf7d3b6bc728285d53b3c06e08a004e2857f398d33ddfad5cfcea9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, directing users to numerous external URLs, with several hosted on compromised WordPress sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, lacking clear user-facing content, which is typical for malicious PDFs designed to exploit vulnerabilities or redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://ksuskalology.com/images/file/dejimosomomovu.pdf
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/37d8359e1a51c71889994c98515a7781/74353594836.pdf
    • https://gastrotest.co/ckfinder/userfiles/files/62120282643.pdf
    • https://m-co.de/wp-content/plugins/super-forms/uploads/php/files/qj7j6eisiph2nqrofvb4k5lsci/wumoguz.pdf
    • https://nilsagame.com/calisma2/files/uploads/40582364236.pdf
    • https://smarttactic.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c874e42e1f5---letakojaf.pdf
    • http://tremonttemplemacon.com/clients/862779/File/moxasodenunuju.pdf
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607224c1437b0---logukazujaxexepuxopuba.pdf
    • https://www.pharmaright.ca/wp-content/plugins/super-forms/uploads/php/files/0d4no277fvr7gmccke3sg0b4g7/93881228292.pdf
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607d2688c9933---kuzuburus.pdf
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/hdekidupendonmhs7bafu9vbi3/2874714420.pdf
    • https://medgarlci.com/wp-content/plugins/super-forms/uploads/php/files/ac06cfd9fa0840dfedb70e47cbf74a65/46703787543.pdf
    • https://grandhotelbulgaria.com/userfiles/file/59064730166.pdf
    • http://jtour.vn/userfiles/file/zexalarusixogaraforameju.pdf
    • http://dtcguild.org/clients/80367/File/68329800478.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fbcd121027---favadisavomexorumuxubiv.pdf
    • http://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa30b519062---82936494651.pdf
    • http://quaretti.it/userfiles/files/ralixanowopawid.pdf
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/4780067a16abe7c84e461e61feb03b2b/mexot.pdf
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/24a8466068ab81e4c1dc2f707f6bc946/lubovituta.pdf
    • http://www.bridalchapel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab976d008e2---jijovirepukozurupekare.pdf
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/a32d033e2d4f9bcc0b94469c5812f090/5964648594.pdf
    • https://stiff.pl/ckfinder/userfiles/files/vugowisadupurazola.pdf
    • http://scamps.biz/userfiles/file/83876645170.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=gravitational+force+is+the
    • 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_off000155b7.bin
338cc954a946a7fbf70b29c55d5e66db99b2ef151e94d540d22e7b387f44db23
pdf-font-stream PDF embedded font (sfnt) at offset 0x155B7 16232 bytes
font_01_sfnt_off00016b92.bin
d748f8c50def8110189b3f8711ee096febf7f352bb52a1ef5a344ec1b915cfc7
pdf-font-stream PDF embedded font (sfnt) at offset 0x16B92 19924 bytes
font_02_sfnt_off00019f66.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x19F66 16792 bytes
font_03_sfnt_off0001b77d.bin
4b6b8ed02cd733040be793c543d529b06cd4782f62d0ee23330f07f514453e97
pdf-font-stream PDF embedded font (sfnt) at offset 0x1B77D 10540 bytes