Malicious PDF — malware analysis report

Static analysis result for SHA-256 b191bdb9075aa16b…

MALICIOUS

PDF

86.9 KB Created: 2021-08-20 12:06:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: aeb74803d529e2b87e2f0369d8d7b191 SHA-1: 456adbfcf0267bec549e2dfc3c1ffabda982900f SHA-256: b191bdb9075aa16bfde3eca42f63b7b541f3de0b9c126b1caa7f88e580631fd1
156 Risk Score

Malware Insights

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

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, with many embedded URLs pointing to potentially compromised or disposable hosting. These links likely serve to redirect users to phishing sites or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 6

  • 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.
  • 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://theprintfactoryvietnam.com/uploads/files/zabinumifozifur.pdf In PDF document text
    • http://alumcity.ru/userfiles/file/texopodakuguxemikeb.pdfIn PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/a26471b33124443e5674bf816d19f5fb/98956609749.pdfIn PDF document text
    • http://train-in-japan.com/images/blog//file/jivebomadokemajuden.pdfIn PDF document text
    • http://edu-family72.ru/content/images/uploads/file/3818654326.pdfIn PDF document text
    • https://angkagenap.com/contents//files/lebasorulasi.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a062e46783e---86421317360.pdfIn PDF document text
    • https://avenue102.com/uploads/file/zovilije.pdfIn PDF document text
    • https://bauarch.bg/files/gukedupegulikavuguro.pdfIn PDF document text
    • https://all-new-wow.com/upload/files/76294541673.pdfIn PDF document text
    • http://ck-buhgalter.ru/userfiles/file/gugenixetuk.pdfIn PDF document text
    • http://www.zywawiara.pl/pliki/fowudeto.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160bd503be85b7---borege.pdfIn PDF document text
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/o4t2r904en927l8nnbre6dafm0/xamotewelovameseniwodu.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16116969e19bef---burelinejivexifiri.pdfIn PDF document text
    • http://bualuang101.com/backoffice/upload/files/7173040576.pdfIn PDF document text
    • http://bowenworktimmins.com/clients/e/ed/ed750a77e36579213b976c45729ba45c/File/23488579614.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/160799ad7bbd23---tobekeminuxafuxivun.pdfIn PDF document text
    • http://wellnesszeewolde.nl/site/data/ws/files/menogim.pdfIn PDF document text
    • https://hamasataccessories.com/userfiles/files/27746143914.pdfIn PDF document text
    • http://michelesherrinlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/21336299816.pdfIn PDF document text
    • http://cicm2015.mist.ac.bd/app/webroot/ckfinder/userfiles/files/31501928315.pdfIn PDF document text
    • http://kusadasidentalclinic.com/img/userfiles/files/53441415127.pdfIn PDF document text
    • https://rumahbaruku.com/contents//files/16258326205.pdfIn PDF document text
    • https://clumba-indoor.ru/files/files/tivofoxatib.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=how+to+get+free+texture+packs+for+minecraft+windows+10+editionPDF 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_off0000ed76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED76 11460 bytes
SHA-256: fd1463c2f39b4fffb5a6b1103a0ad0b15ca2af9b6d6be73800f75aa41b526471
font_01_sfnt_off00010879.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10879 16920 bytes
SHA-256: 8019145f3fb3626e4cb5157df87881604f00796b6dcaad139a6091eeb59cc538
font_02_sfnt_off000134a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134A2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1