Malicious PDF — malware analysis report

Static analysis result for SHA-256 751dc371d44ead9d…

MALICIOUS

PDF

74.3 KB Created: 2021-09-03 11:16:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b237e1b019746700de8333ceef361b17 SHA-1: 58c2508a81593e78cc0799d5700701cca7e8d736 SHA-256: 751dc371d44ead9dece8a4b98af316f2ec742f37df70085af6b48c02fb437e3c
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the nature of the URLs and the heuristic firings point towards a malicious PDF designed to exploit user trust.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://loaamtran.com/files/usersfiles/files/podekoboxapenusebo.pdf
    • http://hanasushi6.com/uploads/files/15534523879.pdf
    • http://tokyoracing.hu/userfiles/file/rukakedo.pdf
    • https://www.medicalart.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160bbc87d8f192---vugobamefenulo.pdf
    • https://loctra.net/userfiles/file/85961469329.pdf
    • http://artecgroupservices.com/imagenes/file/46278706467.pdf
    • https://singaporeroadshow.com/wp-content/plugins/super-forms/uploads/php/files/63fb732c46c1822a57773741ea6ae886/40309007889.pdf
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e5f11b0bdd2---nulejedidunakujukib.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/hmrhl7dasbniubtr7rubahro90/61117623136.pdf
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/68s24ufdsr5r5lj2idnlraammn/88679780396.pdf
    • http://erpos.sk/data/files/84029235675.pdf
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607c56e5c821d---verapu.pdf
    • https://www.asahinafunnels.com/wp-content/plugins/super-forms/uploads/php/files/d05fh2a1kvthe5tadpin9tufln/69070301800.pdf
    • https://www.pal-kont.hu/wp-content/plugins/super-forms/uploads/php/files/f4f3a5fd87e8b22501dbf28aa00b0701/sinowulug.pdf
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/40e6de1782299acd5d9f832896cdad55/79806045803.pdf
    • https://yarsan.ru/wp-content/plugins/super-forms/uploads/php/files/28f29f5946a9879157be4a75e3957caa/59762278761.pdf
    • https://vernadoc.com/wp-content/plugins/super-forms/uploads/php/files/b40220e8ef79633d50327c7b39cf6bc0/gikutunafaleza.pdf
    • http://mikomisushi.com/uploads/files/dagezifijivozuduluwu.pdf
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161306993a78c3---56012579862.pdf
    • http://robertsrucker.com/clients/7/7f/7f5ecd1287ec2152c36a7dc1808edcbf/File/gigogelotozug.pdf
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/1b5b7a77618e458aad3095fe2cb4b94b/panaxuxetemugaxum.pdf
    • http://sigep60s-ncbeta.com/clients/44785/File/bijil.pdf
    • http://architettipassarinmarzotto.com/userfiles/files/reravijedutunogemaro.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=bill+nye+the+science+guy+chemical+reactions+worksheet
    • http://s250801404.onlinehome.fr/img/uploaded/file/65809182902.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_off0000bf2a.bin
b1a5506ec41276eef4dcc82697a8b2e187515da97694e1f30a28e4a39f8f4a72
pdf-font-stream PDF embedded font (sfnt) at offset 0xBF2A 11124 bytes
font_01_sfnt_off0000d910.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD910 16792 bytes
font_02_sfnt_off0000f122.bin
968e987c42b5acca29fe444275985df168bc6d03b7dd734ed8690d1bbd7593de
pdf-font-stream PDF embedded font (sfnt) at offset 0xF122 16076 bytes