Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7cc384c504e4878…

MALICIOUS

PDF

88.1 KB Created: 2021-09-09 04:13:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: fcb518ecb2f70009caafc4ae6d696c32 SHA-1: fdb66bf479cfcf5de8021c3c43264b173018fce4 SHA-256: a7cc384c504e4878f750b71957321b685be03fe1f7f5111a7fcf01b1e14a8971
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to compromised CMS uploads or disposable hosting, suggesting it functions as a link farm. The primary goal appears to be directing users to external, potentially malicious, websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://nomylo.ru/uplcv?utm_term=live+voice+changer+app+android PDF link annotation
    • http://rudolphalexander.com/uploads/files/63889449705.pdfIn PDF document text
    • https://www.stnedu.com/ckfinder/upload/files/50979792242.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613448ec228b8---zunuvipize.pdfIn PDF document text
    • https://jodhpurtravels.com/nbloom/fckuploads/file/nomebapisazavopo.pdfIn PDF document text
    • https://impactmediaresources.com/userfiles/file/tewuxigesowabewebebu.pdfIn PDF document text
    • https://businessincasey.com.au/application/third_party/ckfinder/userfiles/files/37228950275.pdfIn PDF document text
    • http://tokstar.com/_UploadFile/Images/file/61206239013.pdfIn PDF document text
    • https://psfund.org/public/uploads/files/cms_files/73888473950.pdfIn PDF document text
    • http://vitali-schulz-eiskunstlaufen.de/userfiles/files/13598414262.pdfIn PDF document text
    • https://mamproducciones.es/wp-content/plugins/formcraft/file-upload/server/content/files/1613511225dcbf---49027578746.pdfIn PDF document text
    • http://www.europesolidaire.eu/userfiles/files/daziwadalanebojot.pdfIn PDF document text
    • http://socukorglutamatmentesfuszer.hu/ckfinder/userfiles/files/52098559032.pdfIn PDF document text
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/683965680bab7fafbd4b83093498004f/66770858314.pdfIn PDF document text
    • http://lyzph.com/userfiles/file/Fl202109071811386074.pdfIn PDF document text
    • https://jogamiskolc.hu/ckfinder/userfiles/files/63155741423.pdfIn PDF document text
    • https://bhiringisamsankalimandir.org/userfiles/file/73009759778.pdfIn PDF document text
    • http://starfishdowney.com/uploads/files/zuzajoxalajigejapo.pdfIn PDF document text
    • http://litho-and-co.fr/ckeditor/upload/files/wobumero.pdfIn PDF document text
    • http://www.thunderesp.com/ckfinder/ckfinder.htmlfiles/lebibibofetikuzajobabijo.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1613942e08cd04---31733797673.pdfIn PDF document text
    • https://kar360.com/resimler/files/42653754824.pdfIn PDF document text
    • http://szentimresiklos.hu/upload/file/49704968909.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_off0000f372.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF372 18448 bytes
SHA-256: 5bae8f5f0164ce648a90844264e77685f4ce196b0abe9659b1b47b213b7678d7
font_01_sfnt_off00012364.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12364 10504 bytes
SHA-256: 3ab1f35cb3209a29fc244096d7ee95253c7e936195b841f15a700eba0070271f
font_02_sfnt_off00013afd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13AFD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1