Malicious PDF — malware analysis report

Static analysis result for SHA-256 db4315bc15d61622…

MALICIOUS

PDF

69.7 KB Created: 2021-06-09 06:12:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 92677b4247c5a639f4f86985604e401e SHA-1: 00c96634a0e5cae4805e7322805779818fcecb60 SHA-256: db4315bc15d61622e16a575da3b575035d24dab638f7c70a28f5992e30a19030
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://chcial.ru/uplcv?utm_term=practice+questions+for+class+4+maths PDF link annotation
    • https://laetitiabernard.fr/images/file/pupimofutokekedoxesomiwon.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b4cbccbcc1---judasigizatejerawolumiz.pdfIn PDF document text
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/c04f2c4cd7de681ecc899e269c62012a/67930437560.pdfIn PDF document text
    • https://al-farh-iq.com/upload/userfiles/file/72208406146.pdfIn PDF document text
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/480792e70e16d383984aec33de2536fb/taboporulunazobeworemi.pdfIn PDF document text
    • http://timeyear-v.com/userfiles/file/tobuv.pdfIn PDF document text
    • http://dianacb.cz/userfiles/file/bexad.pdfIn PDF document text
    • https://blagoustroystvo24.ru/ckfinder/userfiles/files/gururasuxemafenejeke.pdfIn PDF document text
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/160b9c805cf4bc---13911310280.pdfIn PDF document text
    • http://architettoseneca.com/userfiles/files/sirin.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/160706b225dad8---farumapomifife.pdfIn PDF document text
    • http://www.monts.sk/upload_images/file/tuxemilavodojujarozop.pdfIn PDF document text
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/90a80016950c718fca5fcae869ab81d5/senokijanubelupuv.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1607d07e37a077---fovowawenasebuvog.pdfIn PDF document text
    • http://www.adatechotomasyon.net/wp-content/plugins/formcraft/file-upload/server/content/files/16084034039ac0---17332878806.pdfIn PDF document text
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad88c701e27---49694525349.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d941.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD941 5336 bytes
SHA-256: 3068f12723aabd9090fd0e2b8700b8d74c088a6f2cbfa7047208fc5a7eeb9933
font_01_sfnt_off0000eb42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB42 10436 bytes
SHA-256: bc24f79e2a8a59e1db151c080e20d3295e1ab201764d208926f78017b9344b00