Malicious PDF — malware analysis report

Static analysis result for SHA-256 4df5b11b05cb6abd…

MALICIOUS

PDF

75.8 KB Created: 2021-09-06 21:54:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: dc21cbe7c4b6ddb8201e3a4472e97629 SHA-1: bab1cb64b6a18a5691d8d17c8e8e1a13527a9346 SHA-256: 4df5b11b05cb6abde84ba4b06eed753f3d1e121417be3dcfb8403d74b769c016
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to compromised CMS upload directories or disposable hosting, suggesting an attempt to distribute further malicious content. The presence of a 'download button' heuristic further supports a lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://facilitymanagementassociates.com/survey/userfiles/files/devipofa.pdf In PDF document text
    • http://zatuchlina.cz/upload/file/jinikigajotirigiv.pdfIn PDF document text
    • http://gojjang.com/uploads/files/490779013.pdfIn PDF document text
    • http://danguykhoidoanhnghiephp.vn/Upload/files/fujebezarewuwijav.pdfIn PDF document text
    • http://smenergy.kr/uploaded/file/174193964461123d85d9dcc.pdfIn PDF document text
    • http://chanakyaaerospacedefence.com/userfiles/file/rifif.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/vavujafibawibe.pdfIn PDF document text
    • https://mimpishio2bet.com/contents//files/38637097810.pdfIn PDF document text
    • http://akkoryazilim.com/userfiles/file/lamudidavujukukatutesif.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2df5dae1b5---puloxelagogezixubifuke.pdfIn PDF document text
    • http://www.annaleehuber.com/content_files/file/siwizamebasiwarorixoz.pdfIn PDF document text
    • https://pametnidom.hr/pametne_kuce/userfiles/file/38086765200.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/31b182c02a980250fbe8e6511dc6e035/48970709546.pdfIn PDF document text
    • https://floridaholidayplanner.com/wp-content/plugins/super-forms/uploads/php/files/78750e1c3755fdd090f712dc3ab3e104/95227639848.pdfIn PDF document text
    • https://okazdedziecko.pl/_files/Media/file/53196752542.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/13ce989da3c16691832667be2028366f/wuwogibe.pdfIn PDF document text
    • http://lex-ter.ru/admin/ckfinder/userfiles/files/gawesovabegomufalili.pdfIn PDF document text
    • https://www.agcontraincendios.es/ckfinder/userfiles/files/61680773559.pdfIn PDF document text
    • https://papersacksfactory.ae/images/bulk_images/files/ledumowesomejinabovuvi.pdfIn PDF document text
    • http://swapnakoodu.com/fck_uploads/file/53618180566.pdfIn PDF document text
    • https://ceccarbotosani.ro/userfiles/file/xulamujiresokosaxoje.pdfIn PDF document text
    • https://otterdisplay.com/userfiles/file/roxetab.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=paleontologia+dos+vertebrados+pdf+downloadPDF 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_off0000c060.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC060 18332 bytes
SHA-256: 697764aebf53c30c36a14317b02c793cc9ae95323d52d899a773dcb0172679a9
font_01_sfnt_off0000f029.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF029 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010840.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10840 10964 bytes
SHA-256: 05e18aafbe40a4ae033d74a90f579f02b423f09385824c66d53565118a901b1f