Malicious PDF — malware analysis report

Static analysis result for SHA-256 33bc5736d3f34603…

MALICIOUS

PDF

86.2 KB Created: 2021-09-19 01:44:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d32e73c4d67ee8ba916f56ec9cbba486 SHA-1: 845c8e971ed28289225677b32813a8dd9353e33c SHA-256: 33bc5736d3f34603579399e2b67fa4012ad03054780acd1990eca731c50c59b0
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to various domains, many of which are identified as link farms on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 7

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://coretry.ru/uplcv?utm_term=widgetsmith+apk+android
    • http://leaders-adv.net/userfiles/file/niluxoz.pdf
    • http://mrpennarak.com/user_file/file/65178579025.pdf
    • http://ecohort.com/userfiles/files/77024381143.pdf
    • https://0a3exp.com/upfiles/editor/files/vusoxabekolupopoponu.pdf
    • https://shieldtech.cz/ckfinder/userfiles/files/35566049288.pdf
    • https://maintogelonline.info/contents/files/xorina.pdf
    • http://atek-ent.com/upload/file/wavazakapojekademed.pdf
    • https://tidurmalam2.com/contents/files/noxasujuxozopudosuzebib.pdf
    • https://jmbarrenetxea.soinuenea.eus/files/galeria/files/lenevixixufiriribum.pdf
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/780ee9b8dfa1f343fcbd5249659d32fa/joxisuf.pdf
    • https://kcharp.com/ckfinder/userfiles/files/tamopatavakufukolebuvuli.pdf
    • http://rowadhr.com/app/webroot/upload/files/86517815347.pdf
    • https://przyklejki.pl/userfiles/dazan.pdf
    • https://thefertilizerequipment.com/d/files/18271795850.pdf
    • https://xosobacninh.vn/webroot/img/files/nagiduralobajomutiwan.pdf
    • http://kimwendelldesign.com/ckfinder/userfiles/files/49959253305.pdf
    • http://www.contal-farmer.com/uploads/files/57705047316.pdf
    • http://exmar.it/foto_fck/file/zerexejuwokob.pdf
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/sictbs4ckkic213n8tpgp1kknc/sukoxovexunek.pdf
    • http://hndgyl.com/v15/Upload/file/2021941031311480.pdf
    • http://redemaisfarma.com/userfiles/file/gutodaforedozab.pdf
    • http://www.chiringuitomediterraneo.com/ckfinder/userfiles/files/zovafidekupaj.pdf
    • http://gostium.com/wp-content/plugins/formcraft/file-upload/server/content/files/161429d8ad725d---newepodab.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e8ef.bin
7488d3a4324b1ec4b463997f65ca987fb9786de50ff0cf310724aac322a51e60
pdf-font-stream PDF embedded font (sfnt) at offset 0xE8EF 10876 bytes
font_01_sfnt_off000101a9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x101A9 16792 bytes
font_02_sfnt_off000119bb.bin
a022147827ef6127aca83c355ebfc60e863dd65e0d42496653feba4b424fd223
pdf-font-stream PDF embedded font (sfnt) at offset 0x119BB 18852 bytes