Malicious PDF — malware analysis report

Static analysis result for SHA-256 af58f5bc9052f774…

MALICIOUS

PDF

82.4 KB Created: 2021-08-06 19:55:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: db0893f1249eba20db2c1f3f393a2f56 SHA-1: fd0b369ddf797b4040260a2489245d4feae434c7 SHA-256: af58f5bc9052f774d2c7beabc441228bcbcce8c093383b113cbdfef0b92bfdf9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and a machine learning classifier indicated a high probability of maliciousness. The document contains numerous URLs, many hosted on compromised WordPress sites, suggesting it functions as a link farm. These links likely lead to phishing pages or further malware downloads, aligning with a spearphishing attachment attack pattern.

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://medvor.ru/uplcv?utm_term=exercice+de+lecture+compr%C3%A9hension+ce2 PDF link annotation
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d5d3f78b03---95575860594.pdfIn PDF document text
    • https://ceral.pl/ceral/pliki/file/koretiwide.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c8bfc7d103---80666882759.pdfIn PDF document text
    • http://mdsalon.ru/img/lib/file/diwidazujo.pdfIn PDF document text
    • https://wecafephuket.com/wp-content/plugins/super-forms/uploads/php/files/jvh0n7po9cke7ngu3kv87hnfsh/gilinetejurutusamulesig.pdfIn PDF document text
    • http://ranahytta.com/ckfinder/userfiles/files/65846400714.pdfIn PDF document text
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606d29171e706---vexobilenabejogise.pdfIn PDF document text
    • http://ucity69.com/clients/861769/File/2812307198.pdfIn PDF document text
    • http://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/2967950a3e0743c5874ee7873e6e8032/14023857632.pdfIn PDF document text
    • https://singlespeed-switzerland.ch/userfiles/files/kawavokoveto.pdfIn PDF document text
    • https://www.helmmsp.ca/wp-content/plugins/super-forms/uploads/php/files/e4ff8a4b55117353846baa957f98e359/rapageraguz.pdfIn PDF document text
    • http://presssimayeshahr.ir/pic/file/99171462666.pdfIn PDF document text
    • http://www.mtpartnersfl.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b22e7d3985d---juribomomawaririlemu.pdfIn PDF document text
    • https://boyanbolyarski.com/userfiles/file/66734207669.pdfIn PDF document text
    • http://bahsclassof1965.com/clients/1/1d/1db829f64c2e26d3b32b12ccabba4d7c/File/25904753661.pdfIn PDF document text
    • http://pvsystreports.com/wp-content/plugins/super-forms/uploads/php/files/4tjo4eajks9h538et5lrlkhhg2/97540658607.pdfIn PDF document text
    • https://thewaves.net/wp-content/plugins/super-forms/uploads/php/files/ouc90b64g3b1oi1dj0pv1cbfpg/mabudurutov.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_off0000d8a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8A0 18812 bytes
SHA-256: 619a2c9f32fce889c02526b5d33077d8037299c128de8aba6fd3354c98a9123e
font_01_sfnt_off000107de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107DE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011ff5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FF5 11076 bytes
SHA-256: 8e69735b6a3e3ed2abc212d1859e474ee3586399f072f8ff3d0abe701c4c4965