Malicious PDF — malware analysis report

Static analysis result for SHA-256 1089461b302b3b9c…

MALICIOUS

PDF

92.1 KB Created: 2021-10-04 18:10:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 471ded7aa1031df79a97f4ebcd98068e SHA-1: 1603cdc8ef8764f0fcc5f034e2e56bcae230b4ab SHA-256: 1089461b302b3b9ca0e0d931dda61c6f031669a9b358ca25553079c80459f3d6
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it is a PDF link farm and a callback phishing lure. The document body is heavily obfuscated, but the presence of numerous URLs, some pointing to compromised CMS uploads and disposable hosting, suggests an attempt to redirect users to malicious content. The SE_CALLBACK_LURE heuristic specifically points to a phishing pretext involving phone calls for billing or support issues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://marikakozmetika.hu/editor_up/53809779790.pdf In PDF document text
    • https://shen-su.eu/gfx/userfiles/files/72299018959.pdfIn PDF document text
    • http://plenar.hr/wp-content/plugins/formcraft/file-upload/server/content/files/1613a5e7c98dd4---88577296021.pdfIn PDF document text
    • https://beautifulhairstore.com/upload/files/dodinamatosikelevevebi.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/d2f68ded52ad867e999ca46e05719f40/zakusuwi.pdfIn PDF document text
    • http://euphoriaclub.fun4two.pl/uploads/assets/file/fajovovopevotebu.pdfIn PDF document text
    • https://ever-progress.com/upload/files/busurewumiwosa.pdfIn PDF document text
    • http://poultech.net/d/files/48120651418.pdfIn PDF document text
    • http://ks-system.co.uk/ckfinder/userfiles/files/86795698026.pdfIn PDF document text
    • https://www.corpeverest.com/ckfinder/userfiles/files/31481832664.pdfIn PDF document text
    • https://makenie.com/upload/files/33920803157.pdfIn PDF document text
    • https://bestrecycledautoparts.net/images_i/file/zolusuzaxedatex.pdfIn PDF document text
    • http://basketaci.cz/UserFiles/File/wizujeliwokukutorujub.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/161510759d9bd1---2596204044.pdfIn PDF document text
    • http://ovecollection.com/royal/admin/images/products/file/sevatabefa.pdfIn PDF document text
    • http://elencostruzioni.it/userfiles/files/wuwolalekomeguwetenif.pdfIn PDF document text
    • http://magischtheater.nl/userfiles/file/ritupilezuzodif.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613b0d9f394a3---zukadefivele.pdfIn PDF document text
    • http://vititanon.com/user_img/files/33200976971.pdfIn PDF document text
    • http://launensia.cz/ckfinder/userfiles/files/60166639108.pdfIn PDF document text
    • https://linhan.xelinhan.vn/userfiles/file/gesejorux.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/lolosorulotasofowelef.pdfIn PDF document text
    • https://happen.webasl.com/userfiles/file/rijojexumuzabesumatoz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=dying+light+bow+upgradePDF 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_off0000fcf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCF6 19936 bytes
SHA-256: 6f072b1898277d5df5f47028b7819e18a30687191f04b2856190137d06019d0c
font_01_sfnt_off000131f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131F6 10944 bytes
SHA-256: b9c3d75d8fe64e09aae188611d3581cda53a3805cdf4deaaf3515b8250fe6b6a
font_02_sfnt_off00014ada.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14ADA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1