Malicious PDF — malware analysis report

Static analysis result for SHA-256 8cb76a6b518fa0f5…

MALICIOUS

PDF

87.8 KB Created: 2021-07-17 11:35:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: b178cc45326823ff1e65184615dd8dca SHA-1: f3a3fdc767c074c9f10a84c277880afdaa4e37f9 SHA-256: 8cb76a6b518fa0f5ba73b81bffb8cef9a263d1963554edc7eac307956cd71ed8
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing users to multiple external URLs, with several hosted on compromised CMS upload storage. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to phish or redirect users to malicious content. No scripts were extracted, but the structure and URL analysis point to a malicious link distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 http://paynechapelduquesne.org/clients/9/9b/9b910c66cef3ae2d1bb1fd5804160a19/File/81724432204.pdf In PDF document text
    • https://rivieresoceanie.com/ckfinder/userfiles/files/zejisusovigevefusumigopuv.pdfIn PDF document text
    • http://myucmas.com/userfiles/file/15880137496.pdfIn PDF document text
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/9fc0f4bf41fa2e7aa702e4042e5ef65e/11462858168.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609200edcb83e---refewabiwobumobemat.pdfIn PDF document text
    • http://ahxxzx.com/userfiles/202105/file/bakumowosekezebidijer.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/69c974a261ec485d2372a5ba6f91c378/90251494132.pdfIn PDF document text
    • https://corpusbg.com/files/fck/file/75410013622.pdfIn PDF document text
    • http://cedule-plachty.cz/files/file/farasezefeketenagorodipi.pdfIn PDF document text
    • https://intervalhousehamilton.org/ckfinder/userfiles/files/kevej.pdfIn PDF document text
    • http://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba833f60072---joxozewavof.pdfIn PDF document text
    • https://k-newsletter.com/ckupload/files/koruni.pdfIn PDF document text
    • http://webursitet.org/Files/file/wenido.pdfIn PDF document text
    • http://yds-wcv.jp/free_images/files/nemofelulafifon.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ce9ffc4959---79394488411.pdfIn PDF document text
    • https://www.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/35bvia4ht8mckugp1pc7mvcpjn/85024146478.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1608816c8d0c48---regugasupemivi.pdfIn PDF document text
    • https://daaeportrett.no/upload/file/mepixugu.pdfIn PDF document text
    • https://szaktel.hu/uploads/file/fazejitimokatefipew.pdfIn PDF document text
    • https://nikosdimos.gr/userfiles/file/kojuwirukidofa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=corey+seager+2021PDF 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_off0000f5f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5F4 10380 bytes
SHA-256: 1dd82305ad3ce50dad4d5c48c5671d13d84cfa3789975f3be78d05a3540f0be3
font_01_sfnt_off00010db2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DB2 17172 bytes
SHA-256: bb3608cdf9b25d1328b4849333015ba153474959c49a0a76ca8a12ae33763edf
font_02_sfnt_off00013a96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A96 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1