Malicious PDF — malware analysis report

Static analysis result for SHA-256 a877a605b735c012…

MALICIOUS

PDF

71.2 KB Created: 2021-06-08 14:10:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: 8d627127cba600f8b579b7e19ea6ca90 SHA-1: 305ee338f37b4f143ac9dbfe3bb8abeede9c2323 SHA-256: a877a605b735c0123a93e23bf84a2dc12b21385281ccb2fe7f28761b73219849
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was flagged by multiple heuristics, including a high-confidence ML classifier and ClamAV detection as a phishing trojan. It contains numerous embedded URLs pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of these links indicates an attempt to distribute phishing lures or malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://wastran.ru/uplcv?utm_term=ejemplo+de+texto+expositivo+de+caracter+especializado PDF link annotation
    • http://derma-dts.de/files/file/tujoderate.pdfIn PDF document text
    • http://studiorinaldibedin.eu/userfiles/files/64462731741.pdfIn PDF document text
    • https://www.cibaospalaser.com/wp-content/plugins/super-forms/uploads/php/files/qmdi3hlncvn940m749g3gbs8bm/13345401795.pdfIn PDF document text
    • http://dom-nenilovo.ru/wp-content/plugins/super-forms/uploads/php/files/632cf4f0ee70b92f2dc47201fe0c0f3e/24397779432.pdfIn PDF document text
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/ec4aa85f83db9e076d960f52bce12bda/bijafunuminumovukasiduz.pdfIn PDF document text
    • https://sharidendesignasphalt.com/wp-content/plugins/super-forms/uploads/php/files/031fd84762b342bc139f08d5b86ed9ff/31325017903.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16098369387b18---jofedo.pdfIn PDF document text
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/55a0ade12e9d50b9bb47001d1f5ee951/linupotowupatudu.pdfIn PDF document text
    • https://a1-recruitment.fr/v2011/Files/fck_upload/file/refuf.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/cadc6c80c6b30a5c0b5eff2f384691a7/77347422316.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a46d2fc56cc---sejojukoju.pdfIn PDF document text
    • http://tecsun-moscow.ru/docs/file/8302874022.pdfIn PDF document text
    • http://kaies.cn/upfiles/210525032923291537w1xfic.pdfIn PDF document text
    • https://www.pfgpartners.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb0392bd0f---zudik.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b202983ce81---ditadut.pdfIn PDF document text
    • https://www.rockfallco.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d0412c8603---55991528895.pdfIn PDF document text
    • https://artlabjo.com/userfiles/file/dawekete.pdfIn PDF document text
    • http://dharmapremipariwar.org/userfiles/file/xigiloz.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://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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d585.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD585 5432 bytes
SHA-256: 1f2f9fe6044f94cbc3ddfdd08a01e4465c575709a6cc9fffdfd2abd684ba75b0
font_01_sfnt_off0000e7fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7FC 11720 bytes
SHA-256: 0296a81b3bbb488e209cda39eb0437558fba4ae024ea36983a36dcc43d79c4be