Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c4b35edb29f023a…

MALICIOUS

PDF

96.9 KB Created: 2021-08-02 08:30:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 7c197a47003db9644e518e9dbaa4670c SHA-1: 8e189542f29e9789e65afdd37cc69f10cf2bf7e2 SHA-256: 9c4b35edb29f023a1450173a5a86e768bf297aa8cc06ab8e46040f8c301edfcd
156 Risk Score

Malware Insights

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

The PDF contains numerous external URIs and link farm heuristics, indicating its primary purpose is to redirect users to external sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The presence of multiple links to potentially compromised CMS upload storage further supports this. No scripts were extracted, limiting the analysis of direct execution vectors.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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 https://ketchas.ru/uplcv?utm_term=honkai+impact+3+reroll PDF link annotation
    • http://cogersquest.com/clients/f/f6/f6194b381802d71b6842d6160e8859b1/File/xevifagixumafuxevapo.pdfIn PDF document text
    • http://studiotecnicopetrillo.eu/userfiles/files/10038069578.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/ta2rsj1mq42n13d09cq4380jt6/pojamekafesefex.pdfIn PDF document text
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b87e76a15e---64677507529.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cfbbb18a90a---rezofepifobuxizijonifare.pdfIn PDF document text
    • http://fixmyhelicopter.com/project-new/christianbook/upload_images/file/bapabajos.pdfIn PDF document text
    • http://elcwma.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fosexofasowupepubabezoguj.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16079f5908e375---junakizale.pdfIn PDF document text
    • http://asbufestival.com/uploads/FCK_files/file/29980618265.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/a3c740f1249ad8da8fe0c791eb5048d8/64661046348.pdfIn PDF document text
    • http://clubsahdianagalati.ro/upload/editor/file/8184848958.pdfIn PDF document text
    • https://remoteworkerclub.com/wp-content/plugins/super-forms/uploads/php/files/2bbdb71ad12b397cb2e2c077fdf7a717/9824529427.pdfIn PDF document text
    • https://werbemittelag.ch/upload/file/supikukuvipopez.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ce98415d9b5---xofipoxanipadajo.pdfIn PDF document text
    • http://asupuro.com/upload/save_image/files/jikugiwavugakiz.pdfIn PDF document text
    • https://www.willmarshelter.com/ckfinder/userfiles/files/85968969554.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160d6d5f01a542---54573139059.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e32ac456df0---63465257766.pdfIn PDF document text
    • https://laxmigrouppune.com/wp-content/plugins/super-forms/uploads/php/files/c42e36c2e367ebe1860b20031e4dc738/88152781363.pdfIn PDF document text
    • https://internationalmedia.com/userfiles/file/48816785004.pdfIn PDF document text
    • https://wccia-vastu.com/wp-content/plugins/super-forms/uploads/php/files/92d88c364e9a7e332301f3f2586e0f02/8067695624.pdfIn PDF document text
    • http://raiders71.com/clients/4/41/4134020f2f298c111575624a380fabfc/File/sovawe.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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f896.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF896 1696 bytes
SHA-256: 28c5bcedffb0f63c0f18ed07264126f7c833899b916de9a351f9850be7cb6bae
font_01_sfnt_off000100a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100A2 17484 bytes
SHA-256: 83522f55233ee82f0ed92618cc109633689b2237e3ca85a432588b50eb0f003e
font_02_sfnt_off00012e9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E9E 10624 bytes
SHA-256: 3ef560095c623dc44c86f4c17bb713386eeeb99cdb712df12bc146c63ae2b327
font_03_sfnt_off000146df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x146DF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_04_sfnt_off00015ef0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15EF0 16092 bytes
SHA-256: 9d5144547e0b729630886a3ad3ce48e7da84b0115899dd9c2390406af6f0fecd