Malicious PDF — malware analysis report

Static analysis result for SHA-256 8159f68e6bfa2d02…

MALICIOUS

PDF

70.7 KB Created: 2021-09-26 17:17:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 20a21d9891982e329e7f67fa2b2c1f8e SHA-1: fbb024efc263524c54c0fe040a72da93459a5aaa SHA-256: 8159f68e6bfa2d02b431740ed9d0ddd730915f1acadc0cfc73ebbf5fae453189
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Static analysis revealed that the document functions as a link farm, containing numerous URLs pointing to potentially compromised websites or disposable hosting. These links are likely intended to redirect users to malicious sites for phishing or malware download.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

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 https://smartmedia.ro/app/webroot/files/userfiles/files/51301883535.pdf In PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/81360239757.pdfIn PDF document text
    • http://lynxauto.ru/userfiles/file/17134425335.pdfIn PDF document text
    • https://tttinox.com/upload/userfiles/files/15146238223.pdfIn PDF document text
    • http://lerucherdesanges.fr/userfiles/file/nabegeri.pdfIn PDF document text
    • http://ardechetendancebrut.fr/userfiles/ardechetendancebrut.fr/file/45903084514.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/49f3b5927a8cf54c809aacd231c936c2/24541334830.pdfIn PDF document text
    • https://adikkedua.com/contents/files/74465690218.pdfIn PDF document text
    • http://carneslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/73839552996.pdfIn PDF document text
    • http://pscworld.eu/ckfinder/userfiles/files/6709841521.pdfIn PDF document text
    • https://xn--psg-9lac.hu/files/files/lilotorupoxufuwujof.pdfIn PDF document text
    • http://ajarnveerapong.com/UserFiles/file/wadofizaz.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/4f39cf8c4c7a577d70a4537d66551c84/87470324326.pdfIn PDF document text
    • http://sicompk.com/survey/userfiles/files/20140290856.pdfIn PDF document text
    • https://www.ibyservice.com/wp-content/plugins/super-forms/uploads/php/files/539d2708a27e4f9864e262fafe73ca37/nurusewuroxodanagixopu.pdfIn PDF document text
    • http://hoadondientu-ptp.vn/images/ckeditor/files/nufemapekuvisizej.pdfIn PDF document text
    • https://jeneifogaszat.hu/cikkdata/files/6402091429.pdfIn PDF document text
    • http://fli.edu.mn/ckfinder/userfiles/files/nokun.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d87b52cd2c---31771684033.pdfIn PDF document text
    • http://susasoft.com/upload/userfiles/files/ladafulumupovorafa.pdfIn PDF document text
    • http://aktifithalat.com/resimlerfiles/68893110242.pdfIn PDF document text
    • http://wizclub.net/upload/userfiles/file/29934092403.pdfIn PDF document text
    • http://kaies.net/upfiles/21091911495165453565abg3.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/5c69f8777c59afe926c06612299965ca/52249400922.pdfIn PDF document text
    • https://bancodevida.com/bancodevida/admin/images/image/file/51338181300.pdfIn PDF document text
    • http://fkjz.cn/upload/files/2021/09/202109250906417090.pdfIn PDF document text
    • http://pluimveebeurs.com/userfiles/file/77010825252.pdfIn PDF document text
    • http://medicom.pl/userfiles/file/79361030755.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=simple+pie+chartPDF 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_off0000b406.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB406 16436 bytes
SHA-256: 17fd9fc2dc31a5c44f79d07ab075768c1dbc3c880c7e65ab285627bb589a25ce
font_01_sfnt_off0000ddc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDC7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f5de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5DE 10320 bytes
SHA-256: 04875585013d8f9710fb2739471b2237b0b63363dd2119f746228df5ec469152