Malicious PDF — malware analysis report

Static analysis result for SHA-256 85f08c081b227c0b…

MALICIOUS

PDF

80.2 KB Created: 2021-06-14 00:15:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 9b4ea33f365faf5954b090c7a40df1d5 SHA-1: 2b7bafab552ae4063b934b2c53d8f0c3ceae96b0 SHA-256: 85f08c081b227c0bb1c0b6c80e839a047b7fd520c64e0adc37b3309215bc7fec
156 Risk Score

Malware Insights

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

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 sites and other domains, likely for phishing or malware distribution. The presence of external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic strongly suggest a campaign to redirect users to malicious content.

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://infrive.ru/uplcv?utm_term=911+s5+vpn PDF link annotation
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/c35a98df2903ce06ed653a3e4fbbd28d/zujeremenizawuwefatupiv.pdfIn PDF document text
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f801096795---fimemorilepebonewowose.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079e52f353ca---wavimibotos.pdfIn PDF document text
    • https://givemeit.ru/wp-content/plugins/super-forms/uploads/php/files/e8454328413deec61796ba761ec79b1c/lilexaderukemewufivezofij.pdfIn PDF document text
    • http://austria-ex.com/images/blog//file/dimebexediso.pdfIn PDF document text
    • https://sipare.com.ar/wp-content/plugins/super-forms/uploads/php/files/slgqeouu5eo22tf0itg4p4i8pt/53740486894.pdfIn PDF document text
    • https://thesaddlebank.com/wp-content/plugins/super-forms/uploads/php/files/a558u0u5u3svo3755jaoj97mv9/pipagavovigal.pdfIn PDF document text
    • http://gptools.net/userfiles/file/83041279680.pdfIn PDF document text
    • https://reflexlighting.com/wp-content/plugins/super-forms/uploads/php/files/a6c8243fdb83e8b27ef5e336de57f2e4/5149228658.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/16096b3cae9112---42324315684.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be76aece347---kexeleposevekebozatinopeb.pdfIn PDF document text
    • https://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/ea7oi9he7ntdijiodlp1o3os9h/3318629276.pdfIn PDF document text
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160814753b32f3---68590074881.pdfIn PDF document text
    • https://zold-kommando.hu/files/roladudepoxulalosegos.pdfIn PDF document text
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607b8fda173c2---68324300779.pdfIn PDF document text
    • https://canadianrelocation.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608059ea848ca---1655718601.pdfIn PDF document text
    • http://fanti-fitness.pl/uploads/assets/file/vobebazozo.pdfIn PDF document text
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/16072c2814034b---mekanimamatini.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_off0000fbbe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBBE 4772 bytes
SHA-256: 4f640d12872591c44a00c2c502f9f7445022d9a2636979d1c9d03d71205b4078
font_01_sfnt_off00010c23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C23 11368 bytes
SHA-256: bb077c00ccf5e9b36538d54132830c52d8624ff6250b074b10e17660b8d64a45