Malicious PDF — malware analysis report

Static analysis result for SHA-256 d75d7edb90aa0068…

MALICIOUS

PDF

89.3 KB Created: 2021-07-01 21:01:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 43bc9646150c9be08941bd94abd12da9 SHA-1: 7c7f5332ed304ebaacd698bb69e85c0705c6c378 SHA-256: d75d7edb90aa0068e93bd23087ad1bd26a0f98e295b3f34f06447616d13ba087
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier. It contains a large number of links, many pointing to compromised WordPress sites, suggesting a phishing or malware distribution attempt. The presence of PDF_RANDOM_URL_LINK and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this, indicating a link farm designed to obscure malicious destinations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://nomylo.ru/uplcv?utm_term=the+monster+inside+of+my+head
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/1606f7c3241020---kipupixomejika.pdf
    • http://residencecarlofelice.com/userfiles/files/jewokatufuzexekikejiliva.pdf
    • https://ifacemount.com/wp-content/plugins/super-forms/uploads/php/files/cl2454p4tli8ob2lpn1254muh1/36498761571.pdf
    • http://dermalab.pl/userfiles/file/sigoxepijolimu.pdf
    • https://pellevah.com/upload/files/97232657787.pdf
    • https://egyiksem.hu/uploads/file/52766066997.pdf
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/a2e843d4dd87987fd8cb2f88a23593e4/39586624354.pdf
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/b0991d9991329bd9629f1aca2353acf5/wijonajepilefuzibasudi.pdf
    • http://geobrofab.com/clients/d/da/da7cd3953015cd63472398095fc1fcdd/File/rewuxela.pdf
    • http://doublehappyvstheinfinitesadness.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f754eabdd1---lijigoxakedepixosesi.pdf
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/vuboqmjd5seq5jej9tfslpmrd2/57792051039.pdf
    • https://bizdrive.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/16078e183eafec---13533784136.pdf
    • https://humble-brag.com/wp-content/plugins/super-forms/uploads/php/files/5i8q6oi7l9d9s2fqmte1cr05b6/mosuzokikaxosujupativik.pdf
    • https://atolab.it/wp-content/plugins/super-forms/uploads/php/files/fcddc81205fe7cfe319092d84e3f0909/nerededeponowujosokudobu.pdf
    • http://adamslakeband.org/userfiles/file/wolawakuduxuvebipul.pdf
    • http://leakefamilyreunion.com/clients/63964/File/tebudafe.pdf
    • http://www.hussco-steel.com/husscofiles/files/buxewonevirefowajuz.pdf
    • http://katachizu.com/img/news/files/segefomasomawemelov.pdf
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/7nqq84keovsqjbk8oh7oqilomi/72736848577.pdf
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/af992264f58cd6cde01280bd4fd7ab23/vujojutos.pdf
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/8172b82699bcb0b4074f648410de1eb3/29800662811.pdf
    • https://www.havanasalsa-dance-tours.com/wp-content/plugins/super-forms/uploads/php/files/d9c13e374c375ea3d19abd5a6d754d0f/31498155620.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_off0000fc3a.bin
b3fbc89736a31cea2bc7c644252a0006bdaf2c2aa54aefd1e3ae951dee71f9f8
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC3A 16844 bytes
font_01_sfnt_off000127da.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x127DA 16792 bytes
font_02_sfnt_off00013ff1.bin
fed559df3c50af9268ba3113c47dbc3b69ab4c9cf89b9eda03218b76ea627903
pdf-font-stream PDF embedded font (sfnt) at offset 0x13FF1 10652 bytes