Malicious PDF — malware analysis report

Static analysis result for SHA-256 3caf52f83ca40cd0…

MALICIOUS

PDF

74.6 KB Created: 2021-09-18 23:32:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 986b5437167494fcb7444481bc77f877 SHA-1: 8eb60f74d226d6f2564c4b5db0af3a2f87807437 SHA-256: 3caf52f83ca40cd05bce0bcca413fd5196f6fdb0abf4774f665fabeddecbb5c0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by multiple heuristics and an ML classifier as malicious, specifically identified by ClamAV as a phishing trojan. It contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting a link farm or redirection mechanism. The primary attack pattern involves luring users to potentially malicious external sites, likely for phishing or scam purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://laborke.ru/uplcv?utm_term=new+bollywood+movies+torrent PDF link annotation
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/161420d1ff2b63---tuxagu.pdfIn PDF document text
    • https://www.breastcancerfoundation.in/wp-content/plugins/super-forms/uploads/php/files/f5829d483471fbc2a16945ff648eb9d0/57267466780.pdfIn PDF document text
    • http://bualuang101.com/backoffice/upload/files/jawadajobuxubawe.pdfIn PDF document text
    • http://cableesmaltado.com/d/files/wexidupuxeg.pdfIn PDF document text
    • http://derp74.fooden.com/UserFiles/files/35352423576.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16141659f78626---35137209526.pdfIn PDF document text
    • http://patriabrno.cz/userfiles/files/78933270429.pdfIn PDF document text
    • https://parc-hotel.info/file/6729467816.pdfIn PDF document text
    • http://khamranghaiphong.com/upload/files/resozozar.pdfIn PDF document text
    • http://pcserviszlin.cz/ckfinder/userfiles/files/88348386256.pdfIn PDF document text
    • https://livnica-metalurg.com/images/pages/file/93990759928.pdfIn PDF document text
    • https://maribon.net/app/webroot/files/userfiles/files/kakajova.pdfIn PDF document text
    • https://menu2uplus.com/images/file/83650308304.pdfIn PDF document text
    • https://equalitas.es/userfiles/file/87872541028.pdfIn PDF document text
    • http://jumpstart.mobi/userfiles/file/2273676045.pdfIn PDF document text
    • http://usa-ex.com/images/blog/file/31270143893.pdfIn PDF document text
    • http://ilovehikari.com/uploads/files/47051113703.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133a9f1c4b1e---58461420693.pdfIn PDF document text
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613187c02e8c8---58859457144.pdfIn PDF document text
    • http://hqshop24.com/userfiles/file/fixirete.pdfIn PDF document text
    • http://hattingtoemrerogsnedker.dk/userfiles/file/55105138418.pdfIn PDF document text
    • 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_off0000c030.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC030 10628 bytes
SHA-256: 4e8720938780fe955a96c96926b72d160966d4344176208c238b4bbfa64422b5
font_01_sfnt_off0000d887.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD887 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f099.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF099 17164 bytes
SHA-256: 566ce5b3ec1dd5b2929b72565b0a0c75b1447076b3d9b2526d9cc251c7dd0e03