Malicious PDF — malware analysis report

Static analysis result for SHA-256 a78e9f8c5d3b3a0a…

MALICIOUS

PDF

87.1 KB Created: 2021-06-27 23:15:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: f86c60fee635ef61243b96da7b625aac SHA-1: 28ab3d42fc5422b316241a581aad84f081799b66 SHA-256: a78e9f8c5d3b3a0a85ee503f8b128d04acd0abe43345a67df10c9a7346d18a66
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a machine learning classifier and ClamAV, specifically flagged as a phishing trojan. Static analysis revealed it functions as a link farm, containing numerous URLs pointing to compromised WordPress upload storage and other disposable hosting sites. These links are likely intended to lure users to malicious sites for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://anmoul.com/userfiles/file/10341581433.pdf In PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607e441f75638---jadobadorixajunu.pdfIn PDF document text
    • http://duda-tech.pl/dudatech/upload/file/sonogulizaxufixokituv.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/49098664003.pdfIn PDF document text
    • https://baatco.com/ckfinder/userfiles/files/6469994073.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/e43888574b38a818097752c03e5ca7a1/nurebevezivimupuzimem.pdfIn PDF document text
    • http://vidol.nl/userfiles/file/vunetiteseropikavopuwa.pdfIn PDF document text
    • http://adams-gold.ru/archive/image/file/71380838093.pdfIn PDF document text
    • http://luxe-pools.fr/i/File/27418687008.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/c2f1ksk34oig0kv337jkpr1oo0/2205879106.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16098ba464f892---kozeven.pdfIn PDF document text
    • https://nsck-cykelmotion.dk/userfiles/file/zobepagumol.pdfIn PDF document text
    • http://spoanalyze.com/wp-content/plugins/super-forms/uploads/php/files/bd88c4d4fb9212b1c65415e929ef96d6/popakutagafepexofiwa.pdfIn PDF document text
    • https://www.scilights.com/wp-content/plugins/super-forms/uploads/php/files/8124f1b86f4070015c595d0f28bbe8fd/kinonuzumobexawi.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/16097d6d8b2740---zunorubid.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/k2r2mp5ms7phvai03is7a009pe/zukofojul.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075ccd068daf---89624109218.pdfIn PDF document text
    • http://www.theagentpipeline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cbedec030eb---jedoxudawaji.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/3f159dc3e0529c6a52c48bb176a37fbf/bolow.pdfIn PDF document text
    • http://bertrandetgastineaudesigners.com/userfiles/file/xopipi.pdfIn PDF document text
    • https://monuments-msk.ru/wp-content/plugins/super-forms/uploads/php/files/a99c687ec94137a7f4effe93c8b0aaf4/65637150356.pdfIn PDF document text
    • http://comlark.ru/userfiles/files/kizowewemenusalowazidiwaz.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/tja6dg47qcv60i7kj46npqurc4/bopujapo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=national+women%27s+day+usPDF 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_off0000f11b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF11B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010932.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10932 10620 bytes
SHA-256: 5842e8657d12b311ce916d8b78516ae7a107bd11a13ab9c6245ff6ecc414435b
font_02_sfnt_off00012196.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12196 17776 bytes
SHA-256: 40ef6ffede47d7350f54a0e3a5b72759984f1a3ce1d2ae86e6055c4aceea0a08