Malicious PDF — malware analysis report

Static analysis result for SHA-256 b595e5881e1e6bce…

MALICIOUS

PDF

92.5 KB Created: 2021-06-26 02:57:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 3823b939ccc78f6c222766de27de7294 SHA-1: 369df0e6a77c8c7117c64e926abb2d27dccc2207 SHA-256: b595e5881e1e6bce8b930456f2942449f63f10d5dc6c5652f5fffd3978f1e8dd
156 Risk Score

Malware Insights

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

The PDF contains numerous links pointing to compromised CMS upload directories, indicating a link farm designed to obscure the final destination. ClamAV and ML classifiers strongly indicate malicious intent, specifically identified as Pdf.Phishing.Trojan. The presence of multiple compromised hosts and the structure of the links suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9937

Heuristics 6

  • 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.
  • 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://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/bcf5e687fe269f0fc10b5a47b98b3838/3885137519.pdf In PDF document text
    • http://www.asejnrtigers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607baf7226750---93748410140.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8262bdc881---72573222890.pdfIn PDF document text
    • http://ehomeforeclosure.org/images/file/detidasesisorati.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/04ef5183f0d01b6f0d5166610a4b03a2/penewatumavopumitogabowek.pdfIn PDF document text
    • https://jiptv.nl/wp-content/plugins/super-forms/uploads/php/files/mief99ne3mnbphu6in53ggrp8m/83144356575.pdfIn PDF document text
    • http://shethof.ch/cgi-bin/dynamisch/file/19640111464.pdfIn PDF document text
    • http://zrdb-drogbud.pl/Upload/file/55387935140.pdfIn PDF document text
    • http://ceskylakros.cz/userfiles/file/50880018370.pdfIn PDF document text
    • https://archltginc.com/wp-content/plugins/super-forms/uploads/php/files/20780883d5bdc5d8dd42b27c2146d819/xonozus.pdfIn PDF document text
    • https://law.com.sg/wp-content/plugins/super-forms/uploads/php/files/92028ed61d5fc42eb6d15281107fe323/riwewekajogif.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606f36f55d7f0---fekinimototigemovikeja.pdfIn PDF document text
    • http://www.putnamtaxi.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a3a98661806---54581045278.pdfIn PDF document text
    • http://hesexpo.com/img/editor/image/file/58939622133.pdfIn PDF document text
    • https://zoldlepes.hu/userfiles/file/16249095565.pdfIn PDF document text
    • http://hongshengfish.com/uploadfiles/20210513/210513205608144475d94ip5jy2yd3.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b5fa4555dc---vipijobulu.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072f8626e2e5---45542249114.pdfIn PDF document text
    • https://chicagoportablexray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e574ee1022---jevenofejoxeda.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a1e287f156b---foginepuwutofirita.pdfIn PDF document text
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/fhkfg428iufggdul6i1jmnj61k/resigo.pdfIn PDF document text
    • http://asztalosweb.hu/userfiles/file/57997203911.pdfIn PDF document text
    • https://boumqueur-edition.com/upload/fckeditor/file/bawawaxodesegiwa.pdfIn PDF document text
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/35aba174eda3accd6c187bdfcac442b6/51592639454.pdfIn PDF document text
    • http://kimbuunguyen.com/uploads/userfiles/file/40987810919.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=true+story+horse+racing+moviesPDF 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_off00010121.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10121 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011938.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11938 10876 bytes
SHA-256: 41f16728c82397e1c9430f28a9a96fa0b0a8d5e9dcadcb0713f5b986f6f0ca24
font_02_sfnt_off0001324e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1324E 19760 bytes
SHA-256: ef2e11d78cbfe08d107df1077c46e43261a1a708d36e8bdf344b2ddef433e26d