Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb663cbf5590de99…

MALICIOUS

PDF

105.3 KB Created: 2021-07-15 16:33:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: b74f62f4a7abd66a41e3d0ad76853dbb SHA-1: 88a1bbe9e8ba9723718d8a99143612087701fb66 SHA-256: cb663cbf5590de9944629860e91c3c6a4e177d3fc3e9777db0299f0229c025b0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm pointing to compromised WordPress upload storage, suggesting an attempt to host and distribute malicious content. The presence of multiple unknown URLs further supports the malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9919

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 http://boulderdivorcelaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2a84d3af6e---dulidulemoxizokozetovit.pdf In PDF document text
    • https://www.glasswindowequipment.com/wp-content/plugins/super-forms/uploads/php/files/6e5145b8d46ad4b102d9060aa460a1fd/94306261337.pdfIn PDF document text
    • https://burgaseguros.com/userfiles/file/40832148190.pdfIn PDF document text
    • http://haileylusk.com/clients/e/e6/e6412a3df854040bfb282c4f37eddf02/File/nabofutafadepas.pdfIn PDF document text
    • http://claudiodauelsberg.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160e4a42982d22---kunabarasa.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073f3e3b38c3---75809418991.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b75f8ed765b---68787839592.pdfIn PDF document text
    • http://btc-ltd.com/upload/file/76706104597.pdfIn PDF document text
    • https://dannysacademy.com/ckfinder/userfiles/files/79061887745.pdfIn PDF document text
    • https://eatorhours.org/e-bussiness/fckimages/file/tatisinunapogedut.pdfIn PDF document text
    • https://floridaholidayplanner.com/wp-content/plugins/super-forms/uploads/php/files/839072c0064120d26386e9e42275c9b0/zeredid.pdfIn PDF document text
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/4440dc9702ddf93f33dce8a3236548ac/5661549610.pdfIn PDF document text
    • http://mxm-hosting.nl/img/editor/file/vokimexuwowonukisekefib.pdfIn PDF document text
    • https://remoteyourstaff.com/calisma2/files/uploads/loxor.pdfIn PDF document text
    • https://peiitw.com/Upload/ckeditor/files/fusike.pdfIn PDF document text
    • http://starwindows.ie/ckfinder/userfiles/files/jezibiganos.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16087b99f6e404---zumaz.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/160750144b6134---30246793132.pdfIn PDF document text
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bedb4646e16---resozapokokekodizaxilo.pdfIn PDF document text
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607276f8684e2---2342819348.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/1621f15264f410399358806019e0e361/96163699173.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c93da4d55d7---pimezawodurodofidabubano.pdfIn PDF document text
    • http://www.lnk-creation.fr/upload/file/vuxonu.pdfIn PDF document text
    • http://imailbox.nl/images/uploadedimages/file/19607033889.pdfIn PDF document text
    • https://suativisamsungtaihanoi.net/upload/files/71095942914.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=american+heart+association+cpr+test+answers+2018PDF 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_off0001363e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1363E 17272 bytes
SHA-256: d6988c008f63536d8b2430a8e18013afbfdbdf415367962165820e646928b940
font_01_sfnt_off0001638d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1638D 11164 bytes
SHA-256: fe52f6a744c08eadf16d958734c5ee8cb81c27cd26b46b46593bba1b39ce2e18
font_02_sfnt_off00017d99.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17D99 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1