Malicious PDF — malware analysis report

Static analysis result for SHA-256 ece6cd77f70d5ce1…

MALICIOUS

PDF

89.9 KB Created: 2021-09-07 11:43:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 584f83dac7bd79475aa0fe19614fec9d SHA-1: 7c4d6378cbeddd11e387b4b43a74e48823fd3b45 SHA-256: ece6cd77f70d5ce19cb7b853b7f7d66db94019714ed34bcd39316156c43bcd7c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with many embedded URLs pointing to potentially compromised websites or disposable hosting, suggesting an attempt to redirect users to malicious content. The presence of multiple PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this attack pattern.

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://cheliabinsk.realxenon.ru/uploads/files/zanosami.pdf In PDF document text
    • http://dioceseofniranam.org/userfiles/file/xituzerexuxe.pdfIn PDF document text
    • https://deconkhoemanh.com/wp-content/plugins/super-forms/uploads/php/files/f5cnqb5tnl6l51797bk2f869vf/96528209166.pdfIn PDF document text
    • https://congchung7.com/upload/file/57593707138.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/d0f5e01cd707c9078b8a0f9129d30677/61427917838.pdfIn PDF document text
    • http://veterky.ru/ckfinder/userfiles/files/79688313800.pdfIn PDF document text
    • http://group-anons.ru/userfiles/files/84192846707.pdfIn PDF document text
    • http://barbusci.it/maisUserFile/file/63446190615.pdfIn PDF document text
    • https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/4cbta2750pj2lfmkmhjo6n7b7d/98772573804.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a1cbbbd700---kujagulazivikaginabo.pdfIn PDF document text
    • http://soflocops.net/clients/81266/File/19672621527.pdfIn PDF document text
    • https://nhorizontours.com/userfiles/files/88258708663.pdfIn PDF document text
    • http://ovartec.com/wp-content/plugins/formcraft/file-upload/server/content/files/160885299f11f9---tosejolomomifuzilag.pdfIn PDF document text
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/737eeef33a9fea6f6ce2875c0a7d74af/76549465946.pdfIn PDF document text
    • https://salubrismd.com/wp-content/plugins/super-forms/uploads/php/files/368dfde72b6bd2bac389f82024e0327e/66507666657.pdfIn PDF document text
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/sb8cdjrupob9h0guhl2gtaoadq/55525135672.pdfIn PDF document text
    • https://topclassgreenery.nl/images/file/92210108776.pdfIn PDF document text
    • http://praguetransfer.com/files/file/lelomowibajuxovin.pdfIn PDF document text
    • https://kitapkapla.com/upload/ckfinder/files/73507403845.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=canon+digital+photography+tutorials+pdfPDF 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_off0000fc74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC74 10892 bytes
SHA-256: e149d6c685ebc699598500c2a23487690c6b364ac961ad881ec1a94ae3094f8d
font_01_sfnt_off00011561.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11561 17312 bytes
SHA-256: bb824ed5f35d69c32558933dc8d8c84b6f28d50ff50e8761237285a83d4b62bf
font_02_sfnt_off0001427c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1427C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1