Malicious PDF — malware analysis report

Static analysis result for SHA-256 c461da424611136c…

MALICIOUS

PDF

77.0 KB Created: 2021-06-20 11:44:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: e49e1854bbe022137bb2862810e1671f SHA-1: 16edeb8d4b6fb18aa1ce3cd31c8ea92d429cd9cc SHA-256: c461da424611136c48b0d55403829f0abb67dac40c14a24ebf587e7c7fae9055
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection for 'Pdf.Phishing.Trojan'. The document functions as a link farm, containing numerous URLs pointing to compromised WordPress sites. These links likely serve as a lure to download further malicious content or redirect users to phishing pages. The ML classifier also strongly indicated maliciousness.

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://elbag.net/wp-content/plugins/super-forms/uploads/php/files/c9b4540bccf194eebe618b8028397485/71605002825.pdf In PDF document text
    • https://premiumvipbusiness.com/wp-content/plugins/super-forms/uploads/php/files/adac8af4a6b715abe92ccbc1057859d1/jasunosenalasojuriturodi.pdfIn PDF document text
    • https://vildmarksjagt.dk/userfiles/file/zesofilifomidewezifenujib.pdfIn PDF document text
    • http://kaushalacademy.org/ckfinder/userfiles/files/77416320432.pdfIn PDF document text
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/39c6c425ee6a484171c0134ddfc8502d/70838952126.pdfIn PDF document text
    • https://aryaayur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abe66a2c337---97592117866.pdfIn PDF document text
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/97a142bd32fe54eb1db6f61ed570a892/90613784651.pdfIn PDF document text
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/pod4cbvf9cjdn0t67irt51jfs1/disubokajapawag.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160835e020031c---16892658992.pdfIn PDF document text
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/9c309afb3af36241c3becbd712b67965/mawokowuxusoruto.pdfIn PDF document text
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160c1937c9dd61---juxada.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/37b2225e4860910980ea5a49f3eeb404/nowokofivijewol.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a64eb9a2a82---30680930587.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/779ef9e17ae0dc3c8e4fa59ffdc0fd3a/muporunulelofiwumepa.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=schroth+method+for+scoliosis+pdfPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ef42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF42 5288 bytes
SHA-256: d65e56e517cf9395ddbaff36687bc5a06b2b8a576bdb733c826a1909119f8756
font_01_sfnt_off00010119.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10119 11400 bytes
SHA-256: 885f55cbeef4db709d6406f18bded399754289b35a9f86683171aa8b0550c599