Malicious PDF — malware analysis report

Static analysis result for SHA-256 26c7a5e243e3bcf7…

MALICIOUS

PDF

73.4 KB Created: 2021-07-17 07:09:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 20409e383177d2b8f7195311a5b25889 SHA-1: 075fd6f2a48253f15a4aa886a8219a6863c7025d SHA-256: 26c7a5e243e3bcf76f75bc66dd2ff3e46f2f7c19824247eebaac78d9b3299f1f
156 Risk Score

Malware Insights

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

The PDF file contains a large number of external URIs, many of which point to compromised CMS upload storage and disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent. The primary function appears to be acting as a link farm, likely to distribute further malicious content or for SEO manipulation, rather than containing an active exploit within the PDF itself.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 http://dietetyka-24.pl/images/files/vukubokovotebosiwewusife.pdf In PDF document text
    • https://luxmarketing.agency/wp-content/plugins/super-forms/uploads/php/files/5cochgn0222pe07aebgr2il71s/92018786019.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078085979e7d---nirerusidusomew.pdfIn PDF document text
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/56qi27krs4184nmc25j5q8rao6/vogudedidekafifinutidezi.pdfIn PDF document text
    • http://www.motorradfreunde-toggenburg.ch/up/files/42807591664.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609a3e9b3977e---nobatajamorodumubokuj.pdfIn PDF document text
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/66324290e314efeb9ef0fa6770bfe62e/zuvijef.pdfIn PDF document text
    • http://babamoleskine.com/files/file/95129973481.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/483bfe4d929f0b5831106806ae3e6de2/39179047141.pdfIn PDF document text
    • https://emmaushuis.org/pages/8931216660.pdfIn PDF document text
    • http://fecoil.com/userfiles/file/7645548021.pdfIn PDF document text
    • http://asijskepotraviny.cz/files/file/31243677035.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606c79f2b1f43---daviwijewozugipezogovas.pdfIn PDF document text
    • http://parkhigh65.com/clients/4970/File/duzavifo.pdfIn PDF document text
    • https://www.corridar.com/wp-content/plugins/super-forms/uploads/php/files/6b59q5i4higea3qbtkq61io0lb/83717304529.pdfIn PDF document text
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/a11ifr7lm4kjjvrbggav5b83ji/teposagukikeduzoge.pdfIn PDF document text
    • http://lapenya.cat/imgjovesnaves/file/nuvelewanosazeviref.pdfIn PDF document text
    • http://www.ferm-matic.fr/upload/file/95235470097.pdfIn PDF document text
    • https://yourlightingbrand.com/wp-content/plugins/super-forms/uploads/php/files/e1e1101d9bfcfbf2e5ab4b90585c165b/woximekivorefakobagoxabem.pdfIn PDF document text
    • https://sygimportaciones.com/wp-content/plugins/super-forms/uploads/php/files/lrj0mj8dkgblbqr51nj5bvgi3g/dejib.pdfIn PDF document text
    • http://dobrejaja.com/Upload/file/nugipam.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b1a4b10169---najafowufafozinasupeb.pdfIn PDF document text
    • https://ikima.fr/uploads/file/vomitugax.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160953a5df310a---55124209579.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=mcmurry+organic+chemistry+solutions+manualPDF 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_off0000bbe0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBE0 16552 bytes
SHA-256: d06878ecb5e0101032945cf1a9bc7fc76396d576e53c35c017b3346899dec758
font_01_sfnt_off0000e6f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6F2 10884 bytes
SHA-256: 9659a34680a3789e37861a93145b5bf12631d98d8472cf92b82608195f0164d6
font_02_sfnt_off0000fff8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFF8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1