Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb61fc16b03dd28a…

MALICIOUS

PDF

74.8 KB Created: 2021-09-17 19:14:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 06ae69cea6558dd160585cfcaf5cb320 SHA-1: fed09cb007f056e8caae8d6f89923669ccceaf84 SHA-256: bb61fc16b03dd28ae6680c11ed2f7ac5fd44dbcd332828e254bd5c3957146eb3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs that point to various websites, many of which appear to be compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of creating small PDFs that act as link farms on disposable hosting, suggesting an attempt to redirect users to malicious content or phishing sites. No scripts were extracted, but the overall structure and URL distribution strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://medvor.ru/uplcv?utm_term=the+man+in+the+high+castle+stream+free PDF link annotation
    • https://handientu.vn/userfiles/file/18959172208.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/161416ea3642a1---56662147237.pdfIn PDF document text
    • http://www.aceitunasdelguadalhorce.es/ckfinder/userfiles/files/46786940369.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/161416215ba364---5476335355.pdfIn PDF document text
    • http://sity-luxe.ru/userfiles/file/57763295345.pdfIn PDF document text
    • http://mdsalon.ru/img/lib/file/81966098932.pdfIn PDF document text
    • http://urdu-hadith.com/survey/userfiles/files/63313056942.pdfIn PDF document text
    • https://laser123.com/geektic/files/biduti.pdfIn PDF document text
    • http://loscogliodifavignana.it/userfiles/files/90793136303.pdfIn PDF document text
    • http://0228339500.kad.tw/kads/ckfinder/userfiles/files/15252907805.pdfIn PDF document text
    • https://airflow-skateboards.com/upload/file/lazemonefaf.pdfIn PDF document text
    • http://www.pethouse.es/ckfinder/userfiles/files/91771480865.pdfIn PDF document text
    • http://verzorgingsindex.nl/images/uploads/kefupagivimivotajisaviji.pdfIn PDF document text
    • http://h-p-n.fr/catalogue_dynamique/file/96420765242.pdfIn PDF document text
    • http://huile-de-nigelle.info/userfiles/file/2878770193.pdfIn PDF document text
    • https://www.grdr.org/paidel/ckfinder/userfiles/files/jukoz.pdfIn PDF document text
    • http://wxhsbl.com/ckfinder/userfiles/files/20210914_170213.pdfIn PDF document text
    • http://davcpundri.com/css/file/96011270913.pdfIn PDF document text
    • http://fk-fudosan.1nino3.com/app/webroot/img/userfiles/files/65353665867.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1614076e38d44f---xedewomel.pdfIn PDF document text
    • http://studiopetrilli.it/userfiles/files/21857998447.pdfIn PDF document text
    • http://zbigniewrodak.pl/galeria/file/30654635177.pdfIn PDF document text
    • http://s292376414.onlinehome.fr/datas/imgmail/file/fubuzerifalokuporoxumuves.pdfIn PDF document text
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/161344e8e69fba---94159623859.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_off0000c109.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC109 10628 bytes
SHA-256: 16cb31b0f81c3c70ec1ef67f132b1f69af93c172d2af4f4eace16511e0807f14
font_01_sfnt_off0000d91c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD91C 16744 bytes
SHA-256: 86f78e163cb632244b5a31f4cc3a0a43585c62ecaf86b29787f66f6c1a478ce2
font_02_sfnt_off000103cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103CB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1