Malicious PDF — malware analysis report

Static analysis result for SHA-256 31089792b6830aaa…

MALICIOUS

PDF

68.8 KB Created: 2021-09-24 21:19:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: d49e2147eca38002863ecca6648bbcb3 SHA-1: 8acc075721831e5109b3713206a97a5440c7ede5 SHA-256: 31089792b6830aaa728d79448dfeadeaea2b36a4bef56d314a64566fea2c295a
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to various domains, many of which are hosted on disposable infrastructure or compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The embedded URLs and link farm structure suggest the primary goal is to redirect users to malicious websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://chcial.ru/uplcv?utm_term=best+app+for+phone+transfer PDF link annotation
    • http://steakclubhn.com/campannas/file/8515236911.pdfIn PDF document text
    • http://shrlie.com/upload_fck/file/2021-9-10/20210910095813267818.pdfIn PDF document text
    • https://sofahatinh.com/upload/files/dolikezubuzadamal.pdfIn PDF document text
    • http://skolky.info/foto/images/file/zizusixedexavasuzejaze.pdfIn PDF document text
    • https://www.parquesanalbertohurtado.cl/ckfinder/userfiles/files/69318167686.pdfIn PDF document text
    • http://rootbeadmill.com/upload_fck/file/2021-9-13/20210913235920508531.pdfIn PDF document text
    • https://okinawa4d.com/contents/files/78689655856.pdfIn PDF document text
    • http://tdbakademi.org/userfiles/files/goxopunexesosujenigo.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130f1be72713---32705157214.pdfIn PDF document text
    • http://www.gyndoktors.de/ckfinder/userfiles/files/xotozoxix.pdfIn PDF document text
    • http://jorkurojus.com/userfiles/file/76862871747.pdfIn PDF document text
    • https://primer-spb.ru/files/files/74731393122.pdfIn PDF document text
    • http://innobiztour.com/FileData/ckfinder/files/20210914_0C213EE95527F458.pdfIn PDF document text
    • http://vocal.bpv.su/content/files/files/bafozatoxokukewum.pdfIn PDF document text
    • https://sodigital.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614e06dd90fc9---zevejigenal.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/16133967e06d6b---rajibadoxorimixoleb.pdfIn PDF document text
    • https://myclubowners.com/userfiles/files/61322734274.pdfIn PDF document text
    • https://matfplayer.com/calisma2/files/uploads/ginurirojizotatemid.pdfIn PDF document text
    • https://oz.korytnica.eu/data/files/tarijaforepof.pdfIn PDF document text
    • http://roycraft.ca/userfiles/file/40990415374.pdfIn PDF document text
    • https://primer-spb.ru/files/files/xilidovutulofedinumil.pdfIn PDF document text
    • http://neoneophytou.com/ckfinder/userfiles/files/21099130279.pdfIn PDF document text
    • http://teamtrinity.net/trinitya/file/tixivofenokemig.pdfIn PDF document text
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/c28421b8a2ab1269b364be4a46d36368/60106589488.pdfIn PDF document text
    • http://artechq8.com/beta/uploads/files/75460365665.pdfIn PDF document text
    • 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_off0000b03f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB03F 10368 bytes
SHA-256: 54b629a0d1dc80084c83c9b214ece02b422219d91528d4038978b1367619c6bf
font_01_sfnt_off0000c7ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7AE 15104 bytes
SHA-256: 962cf43b680a7f10c1bba4a9a3d3c43c0a18bdd0a32313d6636fbf359d845a9f
font_02_sfnt_off0000edc0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDC0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1