Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a43442b3778e6f0…

MALICIOUS

PDF

93.5 KB Created: 2021-07-26 17:09:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: d3e076fcc82b798714e7d7801d6a585c SHA-1: 8ead8458a73af298d91f3bdf20bbb5a09d1a8256 SHA-256: 5a43442b3778e6f0343a135acf8fb81f09b91661159055824688a70659942d69
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress upload directories. These links are likely used for phishing or to serve further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c128b82547---15444923909.pdf In PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/ctb358k7cdt99ae9ffreo0ual3/bozubapus.pdfIn PDF document text
    • http://sevimticaret.net/userfiles/file/pulematoraruwunidebogofov.pdfIn PDF document text
    • http://www.molinoag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8a8c77f622---serikabixobofubokip.pdfIn PDF document text
    • http://sskj.pl/userfiles/file/rizozorunibuwetiterede.pdfIn PDF document text
    • http://traiteur-ribot.fr/userfiles/file/80595313688.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fdcd7729e80---zenixaten.pdfIn PDF document text
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606f256287f41---kexepajegukuwudoruwa.pdfIn PDF document text
    • https://www.chauffeur-prive-nice.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16070a8bfad31d---vaforavafiterawup.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607fba6768b8d---16796011834.pdfIn PDF document text
    • http://orlickachata.cz/files/files/pawowemupagumalidubisomu.pdfIn PDF document text
    • https://shayangroup.net/wp-content/plugins/super-forms/uploads/php/files/15e0bd8cef6ec0ab615ecf8e69f04389/sotodesog.pdfIn PDF document text
    • https://travolution.travel/wp-content/plugins/super-forms/uploads/php/files/d3a98bda2aa359db5f629a70d115a53f/kufudutel.pdfIn PDF document text
    • http://busangh.com/attfile/fckimg/file///20210615233551_96287431.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607d47a1c2113---jagomufazajuzewaxexamuli.pdfIn PDF document text
    • https://bilbox.es/wp-content/plugins/super-forms/uploads/php/files/960111d81f211df6fcf96bcf8dfca063/guxikak.pdfIn PDF document text
    • http://houselandia.ru/files/fudasadagafenuka.pdfIn PDF document text
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/0041b70cbacadaeac2b4068cf8f7d280/84253675776.pdfIn PDF document text
    • https://espiber.cl/images/uploadedimages/file/tesikomudi.pdfIn PDF document text
    • https://albawadiroad.com/userfiles/files/28310676761.pdfIn PDF document text
    • http://stlnsk.ru/uploads/file/99279784166.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/dko4jh62d69cgi4tdqcvpb8upn/99064831049.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/160cc00fa9ce03---povojofapo.pdfIn PDF document text
    • https://profbuhotchet.ru/wp-content/plugins/super-forms/uploads/php/files/ee7039a146923f80b0a72833f2365e61/vivamedidopoxozidewabezu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=how+to+calculate+cross+sectional+area+of+a+beamPDF 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_off000106da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106DA 10816 bytes
SHA-256: 51880c9a0ba6c497248c4de45ed843235caabd13d1ed379cadc57ff3bfe671a2
font_01_sfnt_off00011fce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FCE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000137e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137E0 18304 bytes
SHA-256: d5e4e102a8d39896d5a9a60fc97223e8760611ee2012ca9257b9bf638574ce0f