Malicious PDF — malware analysis report

Static analysis result for SHA-256 68b57754a4437fd7…

MALICIOUS

PDF

99.6 KB Created: 2021-07-14 05:41:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 2564612e42367249951e85944d091350 SHA-1: b4e0afc74aa605f3dd39ceb4fbde6daa042552ee SHA-256: 68b57754a4437fd770378a1b0ef2eab8c8d25bf64ebd25b1f34c71ae91b3b9ea
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristic firings suggest the PDF is part of a link farm and contains a callback lure, aiming to trick users into calling a fraudulent number. Although no scripts were extracted, the PDF structure and URL patterns are consistent with phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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.
  • 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 https://www.actionconstructionjax.com/wp-content/plugins/super-forms/uploads/php/files/406c3742f893730703a04c46e7ef426f/fibufib.pdf
    • http://botanicgardenscafe.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a5972aafba4---43203483008.pdf
    • http://chinajessie.com/seadata/data/uploads/img/file/162454015888.pdf
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/9n09n3kulssiekp25t8gmai643/44272369935.pdf
    • http://karat-dobremiasto.pl/userfiles/file/69642826887.pdf
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16080822eaab58---40932080226.pdf
    • http://www.neslihanonur.com/wp-content/plugins/super-forms/uploads/php/files/1615195343dfec5652ccf777f65ed15e/penusad.pdf
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16099b477d1197---83732506588.pdf
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5c647b9c7d---88341397271.pdf
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/4cea5205cc2b1ecbf737df5f7659113a/filegiwabov.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac587695697---geruzatomidorejit.pdf
    • https://aquafilling.com/userfiles/file/15197147281.pdf
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a2fcf3441b9---xepexoberavivedojule.pdf
    • https://ajitcoatings.com/uploads/jeriwexikofaz.pdf
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/r4ico618p1ee3a7qsdetvsupvt/1257410662.pdf
    • https://wpsqld.com.au/wp-content/plugins/super-forms/uploads/php/files/82acfc855485839eef6dd3d9b5fd51ba/56505508880.pdf
    • https://groupunsur4.com/contents//files/9674727379.pdf
    • http://vds-construct.pl/userfiles/file/gozorimobenafafakizajo.pdf
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/0f35efebb327426933a74380a9132b53/54083241017.pdf
    • http://www.sunargrup.com.tr/wp-content/plugins/super-forms/uploads/php/files/qe9csb30hm8scbdhkac28g00l6/majel.pdf
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/bfc06ra80h0rs1tjns8sj1oeh6/36566982358.pdf
    • http://heyumpnd.com/userfiles/file///vuduzusedum.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=flatworms+in+humans
    • 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_off00012661.bin
44ebf3b918dc302fae4d3509947387e974c4627c8664baccea9fbc1cdc1de19b
pdf-font-stream PDF embedded font (sfnt) at offset 0x12661 16952 bytes
font_01_sfnt_off0001529b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1529B 16792 bytes
font_02_sfnt_off00016ab2.bin
705816d182403d5d6dd1e3a708628b9749e1a5747fefb213a3d9b164e01098bb
pdf-font-stream PDF embedded font (sfnt) at offset 0x16AB2 10404 bytes