Malicious PDF — malware analysis report

Static analysis result for SHA-256 13deb2f2b50e0ffd…

MALICIOUS

PDF

87.1 KB Created: 2021-09-18 05:33:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: a6d590e2e948f37894e4fccf58fd93f1 SHA-1: 17b560c46129febc8f204d49c508756043b8b20f SHA-256: 13deb2f2b50e0ffdc54c6aab6befa55e59d31dbd0398306fa11998589447139e
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF document that employs a social engineering lure, instructing the user to install a browser extension or update. This is a common tactic to trick users into downloading and executing malware or providing credentials. The presence of multiple external URLs, some hosted on compromised CMS platforms, suggests a distribution network for malicious payloads. ClamAV detection and ML classification further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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
  • Browser extension / update installation lure high SE_BROWSER_INSTALL_LURE
    Document tells the user to install a browser extension, plugin, viewer, or browser update to view content — a common social-engineering path for credential theft and malware installation
  • 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.
  • 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://pixomot.ru/uplcv?utm_term=quick+messages+android PDF link annotation
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145038e512ca---nafetetakimaso.pdfIn PDF document text
    • https://robert-zauer.cz/userfiles/file/fowom.pdfIn PDF document text
    • https://notarbrazda.cz/userfiles/file/In PDF document text
    • http://rana-international.com/userfiles/files/22322046161.pdfIn PDF document text
    • https://danielstrehlau.com/userfiles/file/rotupejalenisegisoxabaxed.pdfIn PDF document text
    • https://bisnismedsos.com/userfiles/file/52934355989.pdfIn PDF document text
    • http://kccmaul.com/files/files/69627903815.pdfIn PDF document text
    • http://honghuibio.com/d/files/xakukedorus.pdfIn PDF document text
    • http://isotope3.pm-ural.com/uploads/files/fijemuxotive.pdfIn PDF document text
    • https://studiecarriere.it/uploads/file/84323031096.pdfIn PDF document text
    • https://bf-pomosch.ru/wp-content/plugins/super-forms/uploads/php/files/bo035dhrj7sgn8vs4ddubkfsg2/rimewefupogosatafireden.pdfIn PDF document text
    • https://ibshospitals.com/userfiles/file/kupipokixazevugux.pdfIn PDF document text
    • http://boathousebrokerage.com/userfiles/file/soxetewonizulexezumosod.pdfIn PDF document text
    • https://perfecthospitals.com/ckfinder/userfiles/files/gojimupi.pdfIn PDF document text
    • https://accu-split.com/userfiles/files/62845512041.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/bp8pg2qic3cedhi24vsoj9v39d/19957204071.pdfIn PDF document text
    • http://cerrutistudio.eu/userfiles/files/72136906236.pdfIn PDF document text
    • http://phutunggiahungoto.com/uploads/files/22659552219.pdfIn PDF document text
    • http://turinhotelcompany.com/userfiles/files/65100347847.pdfIn PDF document text
    • http://homeopathyhongkong.cn/files/40690528844.pdfIn PDF document text
    • https://netcsemege.hu/ckfinder/userfiles/files/7241875336.pdfIn PDF document text
    • 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_off0000efc0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFC0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000107d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107D7 10820 bytes
SHA-256: 7dd18ea364d423d0f7d2d526d4e4eb00af382b5c30b2c3b31f4c4a10d75d4e1b
font_02_sfnt_off000120aa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120AA 17852 bytes
SHA-256: f1225f90d3e2b052673a4eaa1c94fcf682e3e720ae7f6d656ad4008d7aec73a3