Malicious PDF — malware analysis report

Static analysis result for SHA-256 f85d139ff84c1c21…

MALICIOUS

PDF

85.1 KB Created: 2021-09-13 04:17:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1adc9bcc3d3b367edf59973cafc007dd SHA-1: af45dc5f968f9e7262c1133fee5ad38509fb6088 SHA-256: f85d139ff84c1c21c89390b591b8ca8ea5684ef68f2883da297ff0b149766313
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS uploads. The presence of numerous unknown URLs suggests an attempt to distribute malicious content or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://kimdaiphatsteel.com/Images_upload/files/37629000882.pdf In PDF document text
    • https://wronba.pl/uploads/wysiwyg/file/sepuxol.pdfIn PDF document text
    • http://domkomplekt34.ru/attachments/file/45906039743.pdfIn PDF document text
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/3ed83490922490fa0e9a426bbae12d33/34609786741.pdfIn PDF document text
    • https://bongkartuantakur.com/contents/files/72557766796.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/1613776c2d2200---3609577556.pdfIn PDF document text
    • http://daiquangsico.com/img_duhoc/files/51188037139.pdfIn PDF document text
    • https://clinicscrm.com/img/files/fuxonavupix.pdfIn PDF document text
    • https://parisautotravel.com/wp-content/plugins/super-forms/uploads/php/files/2nbj41n4erdbh7ntkubih21oh6/43531838732.pdfIn PDF document text
    • http://lianbang123.com/uploads/files/202109011601108445.pdfIn PDF document text
    • http://viettranslators.com/webroot/img/files/gasugetu.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/vebojanetositu.pdfIn PDF document text
    • https://exam11.menapoint.com/app/webroot/upload/files/50366081779.pdfIn PDF document text
    • http://loscogliodifavignana.it/userfiles/files/savulevil.pdfIn PDF document text
    • https://agrando.cz/files/file/jupamotexanola.pdfIn PDF document text
    • http://ambvetbrashersclavoghisu.eu/userfiles/files/pibewofo.pdfIn PDF document text
    • https://stephankeppel.com/userfiles/file/52484517875.pdfIn PDF document text
    • http://cageart.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613e93ccb073e---40605476369.pdfIn PDF document text
    • https://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/a4c2a43b5998d698bf15a29c3b3cd487/besezof.pdfIn PDF document text
    • http://baracenter.be/userfiles/file/25409721733.pdfIn PDF document text
    • http://colorfusion.us/admin/images/file/40327535433.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/22ca5489a6d8f39f21fe65fd3b01d9ba/71598403677.pdfIn PDF document text
    • https://northcoteplaza.com/userfiles/file/patebugisuwikuxoveneta.pdfIn PDF document text
    • http://lovec.bg/root/ckfinder/userfiles/files/boxoniwodagopugerosa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=appli+pour+regarder+la+tv+sur+androidPDF 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_off0000e65d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE65D 19080 bytes
SHA-256: b9859b99cda8658994a4e82136d48a57a74fdf2f70ca715a147327e95f8968f6
font_01_sfnt_off00011655.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11655 10712 bytes
SHA-256: eb44fdd1953b0b643dc60ee156cc8afe3e3d46d8abdd47e5d203307ef5079dc6
font_02_sfnt_off00012ee4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12EE4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1