Malicious PDF — malware analysis report

Static analysis result for SHA-256 caf8b78f479ba77c…

MALICIOUS

PDF

84.9 KB Created: 2021-08-16 00:42:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 6a7194730fd378654c02005ed02fe44c SHA-1: 82bb2c370e3388e595b9e4c5969390193217c3d0 SHA-256: caf8b78f479ba77c99f44117a87174858bc6887403eed9a32193791780521c52
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to compromised websites, indicating a link farm designed to redirect users to malicious content. The presence of a callback lure heuristic suggests a phishing or tech-support scam pretext. ClamAV detection and ML classification confirm the malicious nature of the file, likely serving as a dropper or phishing document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 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.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/52a51eeaacc87271b85ee2f7d9a689ae/kovitubilavedulo.pdf In PDF document text
    • https://salubrismd.com/wp-content/plugins/super-forms/uploads/php/files/6b0b20997d01b63ff6ff7694ead14e5e/93884757725.pdfIn PDF document text
    • https://codecs.ro/images/file/55904745472.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/16085e9287b706---44623458671.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c882f89b0c8.pdfIn PDF document text
    • https://wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/fezumofiso.pdfIn PDF document text
    • http://zdrowejaja.com/Upload/file/24248719068.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/5fb51a43d9b5237a77813abeb5ada842/81370467618.pdfIn PDF document text
    • https://bibliotheque-des-arts.ch/ckfinder/userfiles/files/norejaduronolusenufoputap.pdfIn PDF document text
    • http://xn--80affcyoc0ac1f6a.xn--p1ai/admin/modules/ckeditor/ckfinder/userfiles/files/69932422024.pdfIn PDF document text
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/64df1pdkak6kssomnu82klt2cr/92641062148.pdfIn PDF document text
    • http://yossy.biz/userfiles/file/pivovo.pdfIn PDF document text
    • http://ros-grad.ru/fck_editor_files/files/torijukaj.pdfIn PDF document text
    • https://spaslask.pl/wp-content/plugins/super-forms/uploads/php/files/aebhniokfm0v1gf8ld1rb0pvo5/88296503923.pdfIn PDF document text
    • http://www.ambredore.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608d12260bc50---77709219690.pdfIn PDF document text
    • https://wavesmaroochydore.com/wp-content/plugins/super-forms/uploads/php/files/4t3umokrte7opnokd564h99lat/zinovonawisiroxile.pdfIn PDF document text
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/eejihik7vfbt3dpbeh6s98h1hn/nifulivefemofimefafowok.pdfIn PDF document text
    • https://bibliotheque-des-arts.ch/ckfinder/userfiles/files/refixakukaz.pdfIn PDF document text
    • http://biafrapol.pl/pliki/file/91393554332.pdfIn PDF document text
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607800502cf9c---gilira.pdfIn PDF document text
    • https://luminex.pl/upload/file/22305164176.pdfIn PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba3de33c2b8---32991940664.pdfIn PDF document text
    • https://aimhc.com/userfiles/file/fawopavanijevazakijag.pdfIn PDF document text
    • https://landbondcorten.com/attachment/file/ba6d2c0860b555a19fdf99a4c9895930.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=development+economics+gerard+roland+pdfPDF link annotation
    • 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_off0000e3d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3D3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fbe5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBE5 17484 bytes
SHA-256: b4a717656b4267e048249a6364abba66d5c4ba42186a6e88f49af0105ee73499
font_02_sfnt_off0001299e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1299E 11028 bytes
SHA-256: fb17ccbb9837a8caeeb07944eab03fb6c6efb2d46a7db8834da861688b310532