Malicious PDF — malware analysis report

Static analysis result for SHA-256 81ab56a13620e05d…

MALICIOUS

PDF

165.9 KB Created: 2021-08-26 14:43:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 667a0aa94e481f9b22c856116fb188ef SHA-1: 6722c315f94cfcf3242a9f42b961f4ccd44572bd SHA-256: 81ab56a13620e05deb2de80f5bb7cc1299a3bb145f63dee9b60e9d74829e72d5
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised WordPress uploads and disposable hosting, suggesting a phishing or malware distribution scheme. The embedded URLs are likely used to redirect victims to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1611baae4d7243---85974231661.pdf In PDF document text
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/einl2pg7aesvfhgovseei6in9j/sepodimozur.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/278a60120858c64da8c095ba7c0669bc/getuxuzatedemedaxad.pdfIn PDF document text
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/9390f624088d31f7eae1cfa21ff1fbc5/napusoni.pdfIn PDF document text
    • http://airfa.it/userfiles/file/razib.pdfIn PDF document text
    • https://a1-recruitment.fr/v2011/Files/fck_upload/file/gavumavekifajil.pdfIn PDF document text
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609251d961829---lupovisederakokegi.pdfIn PDF document text
    • https://binarbaidfabrication.com/public_html/userfiles/file/56317512278.pdfIn PDF document text
    • http://nissanotogovap.com/uploads/images/files/lezuponubususuvuwudiduj.pdfIn PDF document text
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/0957bc3309b1b7159cb1c04e14bf2e3d/76366288580.pdfIn PDF document text
    • https://hram-uspeniya.ru/ckfinder/userfiles/files/pebowel.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c8876d21d6---wasowub.pdfIn PDF document text
    • http://abw10thstreetne.com/uploads/files/xikusuxaxomuzo.pdfIn PDF document text
    • https://www.web2business.pt/wp-content/plugins/formcraft/file-upload/server/content/files/160a2a0ce528bf---40518790564.pdfIn PDF document text
    • http://harchovyk.com/userfiles/file/10383851947.pdfIn PDF document text
    • https://stefandes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7644687533---gepesogogopirajotuno.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce02281d09e---besurejegijek.pdfIn PDF document text
    • https://www.edmcenter.xyz/ckfinder/userfiles/files/melagivubibe.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1ddc4b4029---kuxujuwitinagil.pdfIn PDF document text
    • http://panhongbo.com/ckfinder/userfiles/site_eachfun_com/files/30735909115.pdfIn PDF document text
    • https://trimix.bg/UserFiles/File/46288058524.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16090d0c0d29b6---69736968860.pdfIn PDF document text
    • https://espaciocultivarte.com/ckfinder/userfiles/files/xatolowubewewajuwireseman.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/f688646e967762504386d92eaab7d70f/91594250763.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16081c0fe943c5---32367617077.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=crucify+your+flesh+daily+scripturePDF 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_off0002161b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2161B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00022e2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x22E2D 29000 bytes
SHA-256: 1ea4a142108662d01484e82470f165ce7620ddaee82a412253d2d919b0e79f0b
font_02_sfnt_off00026e0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x26E0A 10860 bytes
SHA-256: 439d920cf495e05c7667954194067bba443d1c8b23eee0e4f71e5c6f577889c1