Malicious PDF — malware analysis report

Static analysis result for SHA-256 a09c5af79dc92b09…

MALICIOUS

PDF

80.0 KB Created: 2021-09-01 01:04:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: ba719f51cbea66cef82732e046295169 SHA-1: c9abc9f138baf27bc119e85792c395045cb7ce71 SHA-256: a09c5af79dc92b09d812364fcc394194009cafc2d7095d156e41ec7c2a9eca62
116 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by an ML classifier. It uses a callback-phone (TOAD) lure. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 6

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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 http://thepducphat.com/upload/files/sojevedije.pdf In PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/t85bh0kohe9eovpdj5ip1dqm83/jemiz.pdfIn PDF document text
    • http://dges.in/userfiles/file/57817438513.pdfIn PDF document text
    • http://scoutpate.com/userfiles/file/goxizikijuvijisige.pdfIn PDF document text
    • http://lafayetteconnections.com/clients/52818/File/78653929261.pdfIn PDF document text
    • http://vindindex.nl/images/uploads/45109650605.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070d1a6e8f44---35111908400.pdfIn PDF document text
    • http://stepsforstarlight.org/clients/c/c6/c668404594a1c08d975ab50c7bec58f6/File/jajolog.pdfIn PDF document text
    • https://limberhurstgallery.com/imageuploads/file/40490723378.pdfIn PDF document text
    • http://lmyc.net/clients/875386/File/98383086819.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/an7ua1lidms53rj8l66s79rd14/71077330558.pdfIn PDF document text
    • http://schroniskoorzechowce.pl/ckfinder/userfiles/files/zofanurosupidelowe.pdfIn PDF document text
    • https://i-intelli.com/ckfinder/userfiles/files/23233182995.pdfIn PDF document text
    • http://naturalmis.com/userfiles/file/93973573229.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/d61a5850c91c43fbe824db5fac156087/59908187815.pdfIn PDF document text
    • http://pttaccounting.com/userfiles/files/dewiwuku.pdfIn PDF document text
    • http://agrobud.net/uploaded/file/sugenoxerek.pdfIn PDF document text
    • http://richardchong.com/userfiles/files/44878466313.pdfIn PDF document text
    • http://www.expertnutritionadvisor.com/wp-content/plugins/formcraft/file-upload/server/content/files/161258094895d3---72391107059.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=city+of+san+diego+business+license+renewalPDF link annotation
    • http://forum-auto.ru/data/files/gasaraxonedid.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_off0000d126.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD126 11124 bytes
SHA-256: a17823f6d550da3916c074273ee217d774fdb893775fa9fa8ae604efdc8a6a5e
font_01_sfnt_off0000eb2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB2B 18296 bytes
SHA-256: 06f377ac4ed2d4826a7e1a0212ee998232c26bd2789fc3bb85e8a7af155df7b7
font_02_sfnt_off00011ae0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AE0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1