Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdb6a97a89e275bb…

MALICIOUS

PDF

77.4 KB Created: 2021-06-30 17:50:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 36ebf4841ddcac30f510a7057a4b8d82 SHA-1: eae8fad329e7344589255c347eb0c69a63a7fc5f SHA-256: cdb6a97a89e275bbb8bc56eb62dcacc6c3baf32827d9d93806c4951fa9347c43
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with many URLs pointing to potentially compromised CMS uploads or disposable hosting. The document body is heavily obfuscated and unreadable, suggesting an attempt to hide its true purpose, which is likely to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://0a3exp.com/upfiles/editor/files/pukipexugowive.pdf In PDF document text
    • https://bititechnika.com/uploads/file/59671078258.pdfIn PDF document text
    • http://symbioticlifetech.org/attfile/fckimg/file///202105082142_732615073.pdfIn PDF document text
    • http://onlineexpert.in/userfiles/file/xosob.pdfIn PDF document text
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160bfda8473d5f---8286667034.pdfIn PDF document text
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/7b0bddc8265556ec191377f8f39c20ce/12880410881.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/160c286fd16e42---nuzewiwexuji.pdfIn PDF document text
    • http://skolicka.eu/foto/images/file/34903979810.pdfIn PDF document text
    • http://in-dapt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608a1b815457e---kevopaligapezizolazavi.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a06ddf212bc---fazalutemovali.pdfIn PDF document text
    • https://www.straightmyteeth.eu/wp-content/plugins/super-forms/uploads/php/files/e3c176b3bc53a4785a9ba81477859522/govotenudonu.pdfIn PDF document text
    • https://alarrabnews.com/images/content/content/file/pawotaliwawusukerero.pdfIn PDF document text
    • http://antansconstructions.com/ckfinder/userfiles/files/josejaxe.pdfIn PDF document text
    • http://atreve.eu/ubezpiecz/obrazy/file/botideselajumikobufapexiv.pdfIn PDF document text
    • https://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/8768b8caabe46955ba0b8f7693c1b0f8/zaruxaxixo.pdfIn PDF document text
    • https://loan-financial.com/wp-content/plugins/super-forms/uploads/php/files/741271de17550c216879a4bca12654f0/52122529084.pdfIn PDF document text
    • https://baileyelectrical.services/wp-content/plugins/super-forms/uploads/php/files/bol3qepko8uraod101kabdsdua/30875474607.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/c9cfe79b281317cd7a73926a22ca5d2b/34759069159.pdfIn PDF document text
    • http://alternativefitness.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16077f009e3764---manujimezaputajidif.pdfIn PDF document text
    • https://www.femregenx.co.za/wp-content/plugins/super-forms/uploads/php/files/grjdtg1j45e5sg1ccjot8ho6gp/35640791923.pdfIn PDF document text
    • http://sutinlawkrabi.com/ckfinder/userfiles/files/watejaki.pdfIn PDF document text
    • http://xn--80aatg4aaaddkhfhbf3evf.xn--p1ai/ckfinder/userfiles/files/6177081069.pdfIn PDF document text
    • https://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/dca4373b3485a0d741690d7a405c3427/31684596071.pdfIn PDF document text
    • https://wemservice.com/ckfinder/userfiles/files/3591732317.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=ugc+net+home+science+june+2019+question+paperPDF 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_off0000c8bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8BC 16252 bytes
SHA-256: 172f707a51b7a0168f5b3c68f8c24c0c1283bef8e962f5ffe0e6bbfe723f8e8a
font_01_sfnt_off0000f2e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2E3 11620 bytes
SHA-256: 21ec30998b1b5be381c7d761397d50a50bc0903f95ec6d9ffda8522214ce5f93
font_02_sfnt_off00010e1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E1B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1