Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b6af38c557f3b20…

MALICIOUS

PDF

93.4 KB Created: 2021-06-27 00:05:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 9fe1f0c72fe21820fe7a0926f96cc380 SHA-1: 1e7e2bc2ca04699b51697efe41caf338d61f476a SHA-256: 4b6af38c557f3b20595b3aad8b177425fc100afb7836555edf8de483ef89f57e
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains embedded JavaScript, which is often used to exploit PDF vulnerabilities or redirect users. The PDF also functions as a link farm, pointing to numerous URLs hosted on various domains, some of which appear to be compromised CMS uploads, suggesting an attempt to obscure the final destination or leverage compromised infrastructure. The primary attack pattern involves redirecting users through these links, likely leading to phishing pages or further malware downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://leo.tw/upload/ckeditor/files/futabobuvi.pdf In PDF document text
    • http://s-privod.ru/userfiles/file/kobapifenenezukotod.pdfIn PDF document text
    • http://hieuchuan.com/upload/files/98866474882.pdfIn PDF document text
    • http://anjilh.com/uploadfile/file///2021042823355542.pdfIn PDF document text
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/46f6c58122c67f7bedac3ebf07599640/98101838215.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab503a68bdf---48194362626.pdfIn PDF document text
    • https://areicon.com/images/file/84665601738.pdfIn PDF document text
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c020f541799---piziterulexejuba.pdfIn PDF document text
    • http://summithigh75.com/clients/867147/File/71780305003.pdfIn PDF document text
    • https://www.ideaklinikankara.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f6ca0644cb---48641219989.pdfIn PDF document text
    • http://temple.mo/userfiles/file/fijuluvujo.pdfIn PDF document text
    • http://turagent007.ru/userfiles/file/fakapuxawomawazikufajoxa.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acff9a4e92a---76512187102.pdfIn PDF document text
    • https://bdsvieclam.com/upload/files/57691471675.pdfIn PDF document text
    • https://konferencii.ru/js/ckfinder/userfiles/files/fevimamenijatebovujukofoj.pdfIn PDF document text
    • http://guides2alpes.fr/uploads/file/43417100609.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9218cad410---67638467896.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/7cd548ce0daf7909f83058c241885432/giredurozegeta.pdfIn PDF document text
    • https://specialbrands.gr/wp-content/plugins/super-forms/uploads/php/files/a880b9f13c928bc2a8eabefdd9be4d2c/zalinikuje.pdfIn PDF document text
    • https://smilepath.com.au/wp-content/plugins/super-forms/uploads/php/files/4affc01508fb7fb1a601a7211e574e1b/suravofezujoxiwiro.pdfIn PDF document text
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/16093cc43869ef---metujepavoviv.pdfIn PDF document text
    • https://krimgranit.ru/wp-content/plugins/super-forms/uploads/php/files/6ce38e1fc88e12089567ae556c1a6e66/natitikixovob.pdfIn PDF document text
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/kt5qrcddvm9tu3fpgj11pmltej/nopelodexogadugipena.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=ci+in+police+termsPDF 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_off0001076e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1076E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011f80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F80 19416 bytes
SHA-256: f846d3bf103a6e62a7b7f82e07e38e5a3b7f8f7b48ec925d11f8dc3f5fa83d98
font_02_sfnt_off000150f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x150F3 10404 bytes
SHA-256: b0e1328ab0b46beab2df269a6de467ff42fd07504d199961dd1afd5632c2ccfd

Open this report in the interactive analyzer, or submit your own file for analysis.