Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac9f700a7d72d12d…

MALICIOUS

PDF

71.2 KB Created: 2021-10-08 16:00:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 83bf631699f0d40daaea6d8a12294b58 SHA-1: 6779b49c874ac52144060c88c8edf3cb70e97713 SHA-256: ac9f700a7d72d12d2307b7442283742283e37746d369d1b0373ba6302ea9a696
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. The primary attack pattern involves exploiting user trust through a seemingly innocuous document to drive traffic to malicious destinations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://cructi.ru/uplcv?utm_term=one+ear+keeps+popping PDF link annotation
    • http://gk-eventus.ru/admin/ckfinder/userfiles/files/12070400921.pdfIn PDF document text
    • http://sdv.sk/userfiles/articles/file/48779543771.pdfIn PDF document text
    • https://hawkseyetravels.com/assets/ckfinder/userfiles/files/74425301119.pdfIn PDF document text
    • http://vinmexindia.com/uploads/tovina.pdfIn PDF document text
    • http://www.mvdisposal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613720211f1aa---werilozixorupigalu.pdfIn PDF document text
    • https://www.agencesramos.com/ckfinder/userfiles/files/vufidenokikosonedi.pdfIn PDF document text
    • http://homesunshinepharma.com/upload/files/basoramudilu.pdfIn PDF document text
    • http://fabriziocar.it/userfiles/files/37169727865.pdfIn PDF document text
    • http://odnoklassniki-files.ru/images/uploads/files/40399225675.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615fed4e634a0---pibelexusisijusati.pdfIn PDF document text
    • https://marblobaths.ph/app/webroot/img/files/18220213278.pdfIn PDF document text
    • https://inprovituruguay.com/ckfinder/userfiles/files/2860321880.pdfIn PDF document text
    • https://hyosungulf.com/uploads/file/80146691014.pdfIn PDF document text
    • http://stacjaregeneracja.pl/userfiles/file/xurojalozesexekedulirof.pdfIn PDF document text
    • http://zentrumok.com/userfile/files/88294356943.pdfIn PDF document text
    • https://foodvellythailand.com/upload/files/xakafazigotorilumezinupu.pdfIn PDF document text
    • http://soncongnghiepjotun.com/media/ftp/file/96173879340.pdfIn PDF document text
    • http://www.niziointerior.pl/upload/file/mawafolaxusanegimen.pdfIn PDF document text
    • http://photonart.nl/phpcmsys/file/fotozitasuletojonur.pdfIn PDF document text
    • http://studioturina.com/userfiles/files/pufixikoralibunomigag.pdfIn PDF document text
    • http://dolphinkorea.com/files/files/gevodidelufewaza.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/16152e0e72ba79---kijoxonegev.pdfIn PDF document text
    • https://coil.hk/upload/files/manemevolizanire.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_off0000b4cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB4CD 10400 bytes
SHA-256: 2bdbc327c8782bcb76b269b84f9534372cc18fd5084cca6a40955b2b92869b35
font_01_sfnt_off0000cc77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC77 16648 bytes
SHA-256: a21d1e729a12bde0f45af5262f0e238bb149506b45608c46a23057faa0fd935e
font_02_sfnt_off0000f78d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF78D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1