Malicious PDF — malware analysis report

Static analysis result for SHA-256 d739b81dcab43a39…

MALICIOUS

PDF

87.2 KB Created: 2021-07-04 19:46:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 1d6ea85e1e82b63154899611c4e6af1e SHA-1: 9a103a7ad57d3d18388fbf761801b80a676bfa61 SHA-256: d739b81dcab43a3944695ef6385305983a2044181820c53e7a9d54e6ec16b1e3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The document contains a large number of embedded URLs, many pointing to compromised WordPress sites, suggesting it functions as a link farm to distribute malicious content or conduct phishing. No scripts were extracted, but the presence of numerous external links indicates a likely attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://archism.ru/uplcv?utm_term=empire+strikes+back+despecialized+edition PDF link annotation
    • http://www.ellisrasbetonwerke.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607d25227ba56---45841974513.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aec76ad6e77---xenabibim.pdfIn PDF document text
    • https://trichynext.com/wp-content/plugins/super-forms/uploads/php/files/ce042b862dd1a348d0ae3c6bdc6748f4/62074763802.pdfIn PDF document text
    • https://vegas-shop.net/uploads/files/2164559872.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607466daa672c---xojisipulot.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/jedafezovepagujaxalo.pdfIn PDF document text
    • http://hzjksj.com/images/upload/File/fonamijepawukevovubukux.pdfIn PDF document text
    • http://dui-antidote.net/images/userfiles/file/72762488699.pdfIn PDF document text
    • http://capmar.eu/userfiles/file/45159943471.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/texuzofuvulumisovafe.pdfIn PDF document text
    • http://jrmhandling.nl/upload/file/44684458080.pdfIn PDF document text
    • http://circuitoinsulargc.com/documentos/file/niputojonurup.pdfIn PDF document text
    • https://bya-ingenieria.com/ckfinder/userfiles/files/deninadukawigaxo.pdfIn PDF document text
    • https://prsnashville.com/wp-content/plugins/super-forms/uploads/php/files/99098f43e97e81d4491f76e5c9d52e62/98782753581.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1607be9d5c544f---rilimowexavugatufaputa.pdfIn PDF document text
    • https://alternativecarrepair.com/userfiles/file/pugoribuxi.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160b2c12c7c847---juzek.pdfIn PDF document text
    • https://www.modianodesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dd13847b05---34043786025.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/f294ac22f1bef7ba78dcd935a78b84dc/89641309729.pdfIn PDF document text
    • http://ebiocell.com/uploadfile/file///2021052622343341.pdfIn PDF document text
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c5ca805e5e3---66491071581.pdfIn PDF document text
    • https://www.heracles-hotel.eu/wp-content/plugins/super-forms/uploads/php/files/pfjspqqvrp5ts1tlaco6er53vt/62639902206.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/16074c19b3edd9---zogaze.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_off0000efb3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFB3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000107ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107CA 10948 bytes
SHA-256: b4ca15f6a89748e13d33fbc2f23f879a1c3747f672e6e6d3fa1a0cac0d8b2d8b
font_02_sfnt_off000120ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120EE 17808 bytes
SHA-256: 526f8612dcc2745c48cbf481fbce33d4811d9bb6d656f4790c8b56e16cc28df8