Malicious PDF — malware analysis report

Static analysis result for SHA-256 b686f62b63a84593…

MALICIOUS

PDF

85.0 KB Created: 2021-09-15 13:25:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: f84d8bee5f3274b23e5208cabd7ff79d SHA-1: 87afbfac2044188f81432b45ca06d0eff29abb6d SHA-256: b686f62b63a8459310c1b9b703f6462b3501221b13253a8f4aabc7b8b93eeb81
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, indicating a link farm or phishing lure. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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://postele-z-masivu.sk/ckfinder/userfiles/files/xanodidigimupajenixeneke.pdf In PDF document text
    • http://codemessaging.net/ckfinder/userfiles/files/68182943298.pdfIn PDF document text
    • http://buffagiuseppeinfissi.com/userfiles/files/22932927566.pdfIn PDF document text
    • http://stressmanagement-karriere.de/userfiles/file/90154711096.pdfIn PDF document text
    • http://taxplus.in/images/contentimages/files/55875137230.pdfIn PDF document text
    • http://businessvaluationapp.com/fck_files/file/dimekazenifawivexikivetes.pdfIn PDF document text
    • https://sharenkon.com/files/22414568902.pdfIn PDF document text
    • https://kltccompany.com/ckfinder/userfiles/files/muvasamugilumukazusaj.pdfIn PDF document text
    • https://gamedunyasi.com/calisma2/files/uploads/12692367544.pdfIn PDF document text
    • http://storemisr.com/uploads/files/64079965505.pdfIn PDF document text
    • https://pamukoglu.com/userfiles/file/63202701760.pdfIn PDF document text
    • http://shesob.com/file/files/24904145920.pdfIn PDF document text
    • https://tiguan-wiki.ru/file/vuxafotet.pdfIn PDF document text
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138a9ccdf0ff---31508859175.pdfIn PDF document text
    • https://rockyhotelsgroup.com/uploaded/files/pagakiwavuzuvituzolap.pdfIn PDF document text
    • https://kurashi-kyoiku.com/cms/dat/upimg/file/39178616158.pdfIn PDF document text
    • http://tg-focus.ru/userfiles/files/46997914494.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613657f368b07---gabikel.pdfIn PDF document text
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/cd9e428269954bba6ba6332959b3f001/68194564754.pdfIn PDF document text
    • https://zippy-inc.com/app/webroot/userfiles/files/sunevulivuwidupipot.pdfIn PDF document text
    • https://booburger.myagenda.cz/pictures/editor/files/80228950122.pdfIn PDF document text
    • https://mondoaudio.it/img/uploaded/file/3957292318.pdfIn PDF document text
    • https://www.lesson-online.org/wp-content/plugins/super-forms/uploads/php/files/arl8nggbevq86v5fqkacfp62r4/jomezabez.pdfIn PDF document text
    • http://www.forteks.com.br/admin/ckeditor/ckfinder/userfiles/Images/pasagitisavirubovumopug.pdfIn PDF document text
    • https://saintarseny.ca/sites/saintarseny.ca/files/file/96531944993.pdfIn PDF document text
    • https://bibliotheque-des-arts.ch/ckfinder/userfiles/files/xewakuborekadop.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=boostapk+com+valorantPDF 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://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_off0000e580.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE580 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD97 10520 bytes
SHA-256: b64ccb3046e012a05304c5181ea72f02166b04fbe5117819713240914048fd3e
font_02_sfnt_off000115aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115AA 19036 bytes
SHA-256: 21dfc411bfbf30142fdd3760b2b6f6a6e9aa0226f9ae5e3b5056a53f8af39203