Malicious PDF — malware analysis report

Static analysis result for SHA-256 c827d3b50e890937…

MALICIOUS

PDF

74.9 KB Created: 2021-09-01 08:43:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: b5f7d90717716a5c252f51f2b9700e2e SHA-1: 97283b0a0b34eaecfe0425f9004dd5dffc8c587e SHA-256: c827d3b50e8909378e394a47513dac87b829e651bff483c23493b474e079f483
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm and a callback phishing lure, prompting users to call a number for support or billing issues. While no scripts were directly extracted, the presence of embedded URLs and the nature of the heuristics suggest a phishing attempt designed to trick users into engaging with malicious actors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 http://ayurveda-shiatsu-nice.com/upload/files/nukasedowogunonejijuvi.pdf In PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb12c679d08---lonivoz.pdfIn PDF document text
    • http://princeworldwide.com/multimedia/userfiles/file/kijinur.pdfIn PDF document text
    • https://sukienmiennam.com/userupload/files/kikenifexegoloze.pdfIn PDF document text
    • https://www.sehersirin.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076427d10496---fudipafapifugovozituzabeg.pdfIn PDF document text
    • http://nutranghongngoc.com/media/ftp/file/77124490916.pdfIn PDF document text
    • http://sethhukumchandschool.com/userfiles/file/xokemurugu.pdfIn PDF document text
    • http://cn-noah.com/uploadfile/file/62890944458.pdfIn PDF document text
    • http://olgapolyakova.com/files/files/ranopafegojemadosabafaxo.pdfIn PDF document text
    • http://minhphucvietnam.com/uploads/userfiles/file/kepoxije.pdfIn PDF document text
    • https://a5productions.com/home/a5pro/public_html/ckfinder/userfiles/files/rulebekomepadilod.pdfIn PDF document text
    • http://www.binghan.my/userfiles/file/soboxakapexosinajoj.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a961e18a292---jekovesogavogafodeko.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1608554ca080c7---jolap.pdfIn PDF document text
    • http://paliukenas.lt/i/File/70869178547.pdfIn PDF document text
    • http://ekorob.pl/userfiles/file/tinabigafaru.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/160822f3647f88---27999775657.pdfIn PDF document text
    • http://cinebuzz.be/uploads/userfiles/files/vubaw.pdfIn PDF document text
    • https://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609c2df008ce5---67305405261.pdfIn PDF document text
    • http://temple.mo/userfiles/file/67897339412.pdfIn PDF document text
    • https://baptistfriends.org/media/barageziti.pdfIn PDF document text
    • http://www.goldenlantern.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16096fa39ac351---gakeluvinosikoxosimili.pdfIn PDF document text
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e5099cb1d3---32928681672.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160840a0ad855c---36427927177.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/24def34ebb9a0074a63f455b9643c7f7/64300263335.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=buy+set+for+life+tickets+onlinePDF 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_off0000c18f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC18F 10528 bytes
SHA-256: d91c4cfd81d188eeb032fcf69e3beff8cda92d9a868610807ba415ee37bcce33
font_01_sfnt_off0000d9c3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9C3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f1d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1D5 16692 bytes
SHA-256: 354dff22fa19996a96353217cbdc98e9b0fbed554254f80c0ca92194b33f34dc