Malicious PDF — malware analysis report

Static analysis result for SHA-256 91c5d8ca4df39410…

MALICIOUS

PDF

81.8 KB Created: 2021-09-21 09:18:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 6ec75b1b735f19b9fdd6009741e39b90 SHA-1: e3467824d1265e0d6d7cd50d7763649d6bb72088 SHA-256: 91c5d8ca4df3941023ffad5d425649b1b4c49f08e830cc7e2946f3c75f4e036b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to compromised WordPress uploads and disposable hosting, with one URL containing a 'utm_term' parameter suggesting a phishing lure. No scripts were extracted, but the structure and URLs indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://queure.ru/uplcv?utm_term=play+tv+geh+2021+apk PDF link annotation
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16139a2bd5cecb---rokemuda.pdfIn PDF document text
    • http://clear-es.net/yamituki-n/uploads/files/wedape.pdfIn PDF document text
    • https://ariconium.cz/webpagebuilder/ckfinder/userfiles/files/19859717098.pdfIn PDF document text
    • http://446888.top/userfiles/file/pixata.pdfIn PDF document text
    • http://biirbeh.mn/images/content/file/62792533631.pdfIn PDF document text
    • https://vieclamlaocai.vn/webroot/img/files/45762926187.pdfIn PDF document text
    • http://szjg.hu/images/file/23326416228.pdfIn PDF document text
    • http://tulga.ru/editor/files/77468619377.pdfIn PDF document text
    • http://loadcell.vn/Images_upload/files/xetixagujujote.pdfIn PDF document text
    • http://kimbuunguyen.com/uploads/userfiles/file/67599621067.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/162f46f7206829852ae2bbc73e2a6b9f/10491951105.pdfIn PDF document text
    • http://malabarisproducoes.com/arquivos/files/57163948117.pdfIn PDF document text
    • http://reelproductionshd.com/userfiles/file/40779303095.pdfIn PDF document text
    • https://www.hungryalex.com/wp-content/plugins/super-forms/uploads/php/files/25e1bdd40007f21fc43be54a9944f879/kogerugozasurubizole.pdfIn PDF document text
    • http://tajesink.com/Uploadfiles/files/4394509818.pdfIn PDF document text
    • http://www.lukoilmarine.com/ckfinder/userfiles/files/xirepunifipevekixenexam.pdfIn PDF document text
    • http://saatgaamkansarasamaj.com/admin/uploads/files/11347082801.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/161431282158de---wobasigiboluroxojifujuri.pdfIn PDF document text
    • http://domuran.pl/files/file/97725302155.pdfIn PDF document text
    • http://www.maderas-navarro.com/ckfinder/userfiles/files/66924215778.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144100110680---kaboragedatimapewolid.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_off0000d724.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD724 10516 bytes
SHA-256: 6b9af8b20d7be6ff4433b83ece82eae6033bf8edb7019763ef1378d649d2057c
font_01_sfnt_off0000ef61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF61 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010773.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10773 19260 bytes
SHA-256: 426f617e5b8e851176269a2b084db53eb0360e6bc855ae0b5bc9e0a16f24de94