Malicious PDF — malware analysis report

Static analysis result for SHA-256 d97ce519f44904ef…

MALICIOUS

PDF

82.8 KB Created: 2021-09-02 15:44:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 418a492e757a52d21176b89b94178df4 SHA-1: 5f6d9b88e45bc58b4ea81673330d27cd117c2aac SHA-256: d97ce519f44904efdcd91e0535c8a097e8ecfb54568563325e1fb29ec5e78ea6
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically flags this behavior, suggesting the document's primary purpose is to drive traffic to potentially malicious or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/1611558e5c6c16---53308967703.pdf In PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ccfabb1af0---jorukanudidojigisub.pdfIn PDF document text
    • https://romalasergroup.com/userfiles/files/84289431264.pdfIn PDF document text
    • https://autopsrus.com/ckfinder/userfiles/files/jezugi.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a6e6ca026e3---9114404365.pdfIn PDF document text
    • https://latrinquette.com/upload/editor/file/58567186242.pdfIn PDF document text
    • https://feriaesotericadeatocha.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1778a6749e---xulevekedamekegudokat.pdfIn PDF document text
    • http://andrewsexes.org/clients/867461/File/bojajobakemubaferapiluxit.pdfIn PDF document text
    • http://skikk.be/app/webroot/files/userfiles/files/77449354555.pdfIn PDF document text
    • http://jar-ted.pl/file/67735465980.pdfIn PDF document text
    • https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/4859dfac782d1d17b41aac1629e50687/jefiwetonedapoxat.pdfIn PDF document text
    • http://ninda.vn/userfiles/files/reregomisirinubudigubiju.pdfIn PDF document text
    • https://abisspaandboutique.com/nbloom/fckuploads/file/bekoduferomakovopimenu.pdfIn PDF document text
    • https://vnsteeldetailing.com/UserFiles/files/73191561220.pdfIn PDF document text
    • https://yastudio.net/wp-content/plugins/super-forms/uploads/php/files/de709066a7a05daee1394321a7fca96b/xamutajadaketomuma.pdfIn PDF document text
    • https://aeternoplanning.com/ckfinder/userfiles/files/6272360962.pdfIn PDF document text
    • https://bursakaynak.com/userfiles/file/33826815284.pdfIn PDF document text
    • http://zpkprzemysl.pl/ckfinder/userfiles/files/65925879198.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=church+leadership+pdf+booksPDF 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_off0000dfd4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFD4 10880 bytes
SHA-256: 8b19b049978515ac01bc5ae712f3d670697fdb4a985b7a3481bdecdbb6d0ec24
font_01_sfnt_off0000f8dc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8DC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000110ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110EE 17864 bytes
SHA-256: e4365421f72da219c4666b0d1f92910f7b53856ee11e80e83fb9dd8f03d9f1cf