Malicious PDF — malware analysis report

Static analysis result for SHA-256 de35bfaf28ec199b…

MALICIOUS

PDF

76.5 KB Created: 2021-09-18 01:25:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6cee9f5cef3d7b00077ad34252a92d6d SHA-1: f12e839a3f2206cb30f4fccdf7cdb8f955d06956 SHA-256: de35bfaf28ec199b81e88d5acea40b71377afb4cf34a5773889b1b291b9ccfd5
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple heuristics indicating it is a link farm pointing to compromised WordPress uploads and disposable hosting, consistent with phishing or malware distribution. ClamAV also detected it as Pdf.Phishing.Trojan. While no scripts were explicitly extracted, the presence of embedded URLs and the ML classifier's high confidence score suggest malicious intent. The document body is heavily obfuscated and unreadable.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 7

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://themodernla.com/wp-content/plugins/super-forms/uploads/php/files/e8970ca237f5df3630872657d1ed57fc/64656074360.pdf
    • http://corporatiegids.nl/uploads/files/39357360006.pdf
    • http://wildpflanzen-planung.de/file/sesalanomaro.pdf
    • https://rabudiagnostic.com/userfiles/files/jarufiraririjifubutonegas.pdf
    • http://pajurioverslas.lt/ckfinder/userfiles/files/16859147649.pdf
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/29f265125850db85a935d06814287efb/zelatabid.pdf
    • http://dalhousieretreat.com/cote_dor_import/admin/ckfinder/userfiles/files/14990401717.pdf
    • http://e-menu.hu/editor_up/sipemilakirimokofapalofep.pdf
    • https://claudiodituri.it/uploads/xelizedajefejev.pdf
    • https://rosettes.it/userfiles/file/18822460418.pdf
    • http://cornaredo.gattinonimondodivacanze.it/themes/userfiles/files/7386046394.pdf
    • https://dafelia.com/files/79891655196.pdf
    • http://afghansolar.com/userfiles/file/jetebapukijazisimobasufo.pdf
    • https://nikoljski.com/ckfinder/userfiles/files/wobiwawavogotibej.pdf
    • http://hoangminhceramics.com/app/webroot/uploads/files/75150532268.pdf
    • https://noithathoaphat11.com/upload/files/vekuguxire.pdf
    • https://hmanagement.net/userfiles/file/7587591431.pdf
    • http://barbusci.it/maisUserFile/file/81819397670.pdf
    • https://praktijk-fix.nl/userfiles/image/file/58524046465.pdf
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fe778e83f3---fajirugitid.pdf
    • http://mateuszkucharski.pl/admin/file/13128429596.pdf
    • http://thesciencenetwork.org/uploads/files/33683569345.pdf
    • https://exihomes.com/userfiles/files/rukakibipezofefowogadoxib.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=zxing+qr+code+library
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b2d3.bin
c4cbd446e6f3040e514656fe0485de2005c103a5e185322f8c4ff1df2e588b2f
pdf-font-stream PDF embedded font (sfnt) at offset 0xB2D3 10744 bytes
font_01_sfnt_off0000cb16.bin
827b22fba1b03e8c03b00a40fbff5ebc3efb111614d24b7b8adefed9a3ad2dfe
pdf-font-stream PDF embedded font (sfnt) at offset 0xCB16 17260 bytes
font_02_sfnt_off0000f64f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF64F 16792 bytes
font_03_sfnt_off00010e60.bin
b17e3c388ca520c70044df51a505a8c8de3d1ca9b2e495c629779bc8d31aca59
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E60 16148 bytes