Malicious PDF — malware analysis report

Static analysis result for SHA-256 ccf0a79ab18f2e1a…

MALICIOUS

PDF

86.4 KB Created: 2021-07-01 21:45:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 49439f903b790a0e3842773a34567d9f SHA-1: a18cb27a7393860a7914135344ef147fe24b8431 SHA-256: ccf0a79ab18f2e1ad04027484aaaacde30e17666ad6236bfe56904083b4796e8
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to compromised WordPress sites, as indicated by the 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' heuristics. The ML classifier and ClamAV detection further support its malicious nature. The primary attack pattern involves directing users to potentially malicious content hosted on these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9848

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://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/de7c7069921473f817965f0e27226887/remidebotenux.pdf In PDF document text
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/160b9b0433e3f5---39311935488.pdfIn PDF document text
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c15c39aa6a3---36605656501.pdfIn PDF document text
    • https://www.nuyew.academy/wp-content/plugins/super-forms/uploads/php/files/57d681011ea02b0ddae3d784e2b615b7/28568237136.pdfIn PDF document text
    • http://mg001.cn/upload_fck/file/2021-5-18/20210518072718202508.pdfIn PDF document text
    • http://marta-galan.com/files/varios/file/47197395638.pdfIn PDF document text
    • https://anaksemut.com/contents//files/73649989854.pdfIn PDF document text
    • http://project-st.ru/userfiles/file/madetalajefof.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/bc3ba1691b8058091aa3edfc9428c5c2/79504437701.pdfIn PDF document text
    • http://businesslegalgroup.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/foxub.pdfIn PDF document text
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/160810000640ab---39165856780.pdfIn PDF document text
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160c50b3fbe98b---2417910272.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/160c997bdd9b21---9581349349.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c94d8dd6254---kosuzanusesekujukokozeb.pdfIn PDF document text
    • https://canadianrelocation.net/wp-content/plugins/formcraft/file-upload/server/content/files/16083ed2a7c2cb---79635010419.pdfIn PDF document text
    • https://hzautomatisering.nl/userfiles/file/75275661122.pdfIn PDF document text
    • http://anhuizpyy.com/upload_fck/file/2021-5-2/20210502003418330519.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/16093a01cb1831---potitumadububasak.pdfIn PDF document text
    • https://www.albispanaderia.com/wp-content/plugins/super-forms/uploads/php/files/82bc0a25d2ed42fe51f10720412c523f/34996939892.pdfIn PDF document text
    • https://digireg.cz/upload/mipitukazolabon.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/db13c2aef38442d5b3a2cd7f47e3d962/koxonetojidapeki.pdfIn PDF document text
    • http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f6232bc14b---pixolon.pdfIn PDF document text
    • https://krassimirtaskov.com/userfiles/files/fejipojijilusulusali.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/399e8b9fae63d91a2adeefd670ae6b4d/11763475966.pdfIn PDF document text
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/b4c367123e13cdb2d80a7d4aacdf23b8/37012893539.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf93b31aa29---16174564950.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=dry+mouth+in+winterPDF 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_off0000f09b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF09B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000108b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108B2 10300 bytes
SHA-256: 40f19882f8aee5714699e4747998efb1be3e1e8085bae033ae785a54275ecb32
font_02_sfnt_off00011fc6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FC6 17300 bytes
SHA-256: fcfc11de3b49491da43380dbbafabe4969fb59e0d0b8ef8b13e1d299f7199dc1