Malicious PDF — malware analysis report

Static analysis result for SHA-256 4220af4cb965193a…

MALICIOUS

PDF

83.9 KB Created: 2021-09-18 17:07:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 53f8280c11bad7fa998ca960abe1440e SHA-1: c1a7bcd4f1b693b4dea001d587d9e28bd16f3c2f SHA-256: 4220af4cb965193a20b92fca50dc966ff299469a3983e07fb58ad5563eedff9d
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious File

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection for 'Pdf.Phishing.Trojan'. It functions as a link farm, containing numerous embedded URLs that point to potentially compromised websites or disposable hosting. The ML classifier also strongly indicated maliciousness, supporting the phishing and trojan classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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 http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613ac6be95a4d---pedobinejupusisebetigob.pdf In PDF document text
    • http://pneusmarene.it/images/file/zexobuputi.pdfIn PDF document text
    • https://frontiermyanmar.com/sites/all/libraries/ckfinder/userfiles/files/surazeneputum.pdfIn PDF document text
    • http://bradzo-ep.com/uploads/files/5844424487.pdfIn PDF document text
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/3a9fca00d33443fe3e18062597383140/kijomumefafa.pdfIn PDF document text
    • http://mlsy.cz/images/file/files/rojowon.pdfIn PDF document text
    • https://xn--80aggmy8c6c.net/UserFiles/File/mugerudoxigegup.pdfIn PDF document text
    • http://thecargonepal.com/userfiles/file/77726498295.pdfIn PDF document text
    • http://dywin.com/uploadfile/files/33027292653.pdfIn PDF document text
    • http://smelawservice.com/file_media/file_image/file/vofosasideverodaf.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613be5dd41874---30836713154.pdfIn PDF document text
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/cde81f0dc4a45325e16d09bf8ee621a7/dedujumolijulawezazeb.pdfIn PDF document text
    • http://chatfieldfarms101.com/userimages/14343969.pdfIn PDF document text
    • https://huaienclinic.com/uploadpic/files/16329897007.pdfIn PDF document text
    • https://dispecom.com/cms_dispecom/sgi_userfiles/userfiles/files/73946847519.pdfIn PDF document text
    • http://rickgrisolia.com/userfiles/files/36092420318.pdfIn PDF document text
    • http://robbes.nl/media/files/13901636212.pdfIn PDF document text
    • https://magicdiscoradio.hu/userfiles/file/85480283595.pdfIn PDF document text
    • http://zopos.zohukum.com/ckfinder/userfiles/files/telafatisefapuxivifofurog.pdfIn PDF document text
    • http://zbraneklapka.cz/ckfinder/userfiles/files/tipijotamamodesoge.pdfIn PDF document text
    • https://coevent.ru/upload/files/43869212772.pdfIn PDF document text
    • https://www.restaurant-latableedevercel.com/ckfinder/userfiles/files/susibuguvorokavo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=ipad+pro+11+inch+2021+price+in+pakistanPDF 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_off0000dd03.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD03 19672 bytes
SHA-256: 256c960832e4ba4da4549c01739902b3a44dfe0f2b1133b2bc824245749787d2
font_01_sfnt_off000110d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000128e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128E7 10900 bytes
SHA-256: 3552b21935e3f1b15caf82d616dcf56b6a47eadb210e52380e11c4e15ce6fd5a