Malicious PDF — malware analysis report

Static analysis result for SHA-256 2d737509e6cee3e8…

MALICIOUS

PDF

76.1 KB Created: 2021-06-10 18:33:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: ddd0922a9983d0079795c3a24c9a497d SHA-1: 75a5ef87e520491a05014c89bc451d5912f3a1d8 SHA-256: 2d737509e6cee3e834da0a8954a1d8162d3b71bf8065a5457315986b387d0df7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF document contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, suggesting a link farm designed to distribute malware. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or trojan distribution. The document body, though heavily obfuscated, contains references to 'wkhtmltopdf' and 'Qt', indicating it was generated by a tool rather than being a legitimate document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://smidgel.ru/uplcv?utm_term=ansi+c+programming+book+pdf+free+download PDF link annotation
    • http://vietxetai.com/wp-content/plugins/super-forms/uploads/php/files/9hkbkhkfau6rilent1867ldlap/xezekojadimitadokota.pdfIn PDF document text
    • http://sicilalluminio.it/userfiles/files/42759893181.pdfIn PDF document text
    • https://arerp.kr/data/file/%5C/gobiwuzikom.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16088d31f21424---foleb.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608c1a4d2931e---zifalazerofinakawazowu.pdfIn PDF document text
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/4omhupimr716sf08g1e0m8ap0l/65656587852.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096d353488b9---34749358766.pdfIn PDF document text
    • http://falconartistmanagement.com/ckfinder/userfiles/files/wixepikukadowi.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/1606f0ec072089---xijosenurukunirixino.pdfIn PDF document text
    • https://europeancustomtailor.com/wp-content/plugins/super-forms/uploads/php/files/104b05ef586db27554764f235cb26f13/3522856611.pdfIn PDF document text
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/4435f0348ae027347c56c1c08fc98a54/54277081864.pdfIn PDF document text
    • http://woodsfamilypride.org/clients/2/2c/2c83419adcf4927d74d3defe18342386/File/tezufapegujusemaj.pdfIn PDF document text
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac910913325---97604221757.pdfIn PDF document text
    • https://mziagroup.com/wp-content/plugins/super-forms/uploads/php/files/k2lgs7egb72d4j3itcrgre4aqu/sufibegarobarufolexowifuk.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/ht5hcp92vkl1bpubu3j644roq1/27366057622.pdfIn PDF document text
    • http://x-site.by/upload/editor/files/nenademi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eaa9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAA9 5760 bytes
SHA-256: 173beef387593b08baf1ded00814ecd1b7aa67d2407f35de3e5812d5a0ee8d9f
font_01_sfnt_off0000fe46.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE46 11260 bytes
SHA-256: 1919aa8b7fbed84607385a8e5cf25c2caf3876b9c78155b2c918f6ec27e010d4