Malicious PDF — malware analysis report

Static analysis result for SHA-256 b2f582dc2d242523…

MALICIOUS

PDF

72.3 KB Created: 2021-10-02 19:07:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 27d90896cf1ea38cf05a751f0d08b135 SHA-1: 9bbbc693e0ca2ccc35f811ce8458510f70127ad7 SHA-256: b2f582dc2d2425233ebc676eacc30a6a1dbb486090d6557513431b584267f7c7
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple unknown domains, some of which are hosted on compromised WordPress sites. Embedded JavaScript streams are present, suggesting potential for further malicious actions like phishing or malware delivery. The primary attack pattern involves luring users through a deceptive link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://lsbwg.com/ckfinder/userfiles/files/20210928/2250405438.pdf In PDF document text
    • http://xn--j1aai7d.xn--p1ai/userfiles/file/32793768573.pdfIn PDF document text
    • https://www.barefoothoa.com/webroot/js/ckfinder/userfiles/files/ferenu.pdfIn PDF document text
    • http://jlsxjy.com/right/UploadFile/file///2021100123240373499.pdfIn PDF document text
    • http://standartbio.com/fckfiles/file/fekowakagopuwina.pdfIn PDF document text
    • https://tourpon.kr/FileData/ckfinder/files/20210913_3B21E856226DD77E.pdfIn PDF document text
    • https://kenkochaya.com/user_data/ckfinder/files/vonaniwawatetow.pdfIn PDF document text
    • http://squarcialupirelaxinchianti.com/writable/public/userfiles/file/998789958.pdfIn PDF document text
    • http://qianxish.com/ckfind_image/files/52050755083.pdfIn PDF document text
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/161314e087ef74---gerenipo.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613de1bb51964---21597290834.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/4vbm929fj6eji7iv8vdpm81u2m/81434102413.pdfIn PDF document text
    • http://drivingschool-brno.eu/files/jubopamijudorirevif.pdfIn PDF document text
    • https://www.nickelmarket.co.za/includes/ckfinder/userfiles/files/62315645629.pdfIn PDF document text
    • http://incomingmakedonia.com/files/files/fugupo.pdfIn PDF document text
    • https://on-call-anatomist.org/ckfinder/userfiles/files/datosexobagox.pdfIn PDF document text
    • http://gpba.ge/admin/ckeditor/ckfinder/userfiles/files/22729920834.pdfIn PDF document text
    • http://www.egavilanes.com/ckfinder/userfiles/files/zokasodoruwi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=medications+that+cause+impotencePDF 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_off0000b29f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB29F 18972 bytes
SHA-256: ad40a011f101796c8beb93c41e27b8db40b6e052b3522ba47b9baca16b9adb40
font_01_sfnt_off0000e389.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE389 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fba0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBA0 10728 bytes
SHA-256: 54368fd40e98446ac9433b391046035da18745541219e3b787e43e4684d6a7ea