Malicious PDF — malware analysis report

Static analysis result for SHA-256 272465fdae090767…

MALICIOUS

PDF

82.1 KB Created: 2021-09-07 18:22:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 2a41fd76ca88ff2fd7a407d8face2a78 SHA-1: a85271e1a2b85c35c3a611f8557c35251d29ee59 SHA-256: 272465fdae09076701604ad59671772415d6403a971349db153a9c23606e061d
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that point to other PDF files hosted on various domains, many of which appear to be compromised WordPress sites. The ML classifier strongly indicated maliciousness, and the structure suggests a link farm designed to manipulate search engine results or distribute further payloads. No scripts were extracted, but the presence of external links and the ML detection point to a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • 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://laborke.ru/uplcv?utm_term=comparative+and+superlative+exercises+for+beginners+pdf PDF link annotation
    • http://smartcookieacademy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612cd41fcac2a---molipizubulopipuxufuvuru.pdfIn PDF document text
    • https://casabresciani.it/uploads/file/gisebexe.pdfIn PDF document text
    • http://vector-mebel.ru/uploads/files/89743511586.pdfIn PDF document text
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/31450908302.pdfIn PDF document text
    • https://www.vedaaz.com/wp-content/plugins/super-forms/uploads/php/files/727919c0a82d9f178fb748cc92cf9e91/ketupomexakozajowejoxefet.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b68f31d95d---4438536481.pdfIn PDF document text
    • https://coimbatorepressclub.com/FCKeditor/userfiles/file/44165752571.pdfIn PDF document text
    • https://monacollection.ua/wp-content/plugins/super-forms/uploads/php/files/cbc93acb15a49b79015ac6182eeb9b4b/77777237342.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/ffcf757f80ecbd9fc1c55d2fd22b1ff6/18102866902.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16114a073aa7cc---lowaguwiwaxejuwupuweleni.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612612382b737---85287089251.pdfIn PDF document text
    • https://krone-murten.ch/userfiles/files/67521122851.pdfIn PDF document text
    • https://maryamghiasi.com/images/upload/files/52217702970.pdfIn PDF document text
    • http://adaviestransportltd.com/userfiles/file/dafenopisusegifimise.pdfIn PDF document text
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/aafa589efcf2a589061fdd9d88f28522/3046879261.pdfIn PDF document text
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/csccu9540vgatun3iqu3t95sci/52619583457.pdfIn PDF document text
    • https://fjordancv.info/wp-content/plugins/super-forms/uploads/php/files/cb0051474b8360a415f916da43ea26b9/wikegaliduwaxupilabekego.pdfIn PDF document text
    • https://fobiy.net/wp-content/plugins/super-forms/uploads/php/files/fd369cbf48b57a356ebfaa83edc2f836/68590754473.pdfIn PDF document text
    • https://charming-dc.com/uploads/files/202109010759091667.pdfIn PDF document text
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/da4f66a8efe07e42933517810a045b1e/vuvuwaxarurudixozuzaruk.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16083eb66ac083---fotuxuwizon.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133c590aca89---zotanumijoludakotaxir.pdfIn PDF document text
    • http://ofitecnic.es/files.ofitecnic/fck_up/file/supotimalaganavaxudub.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2c29be9f66---15514677628.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_off0000db81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB81 17200 bytes
SHA-256: aea388cf4ba9c721124295df2215d8e9d0da8abdfc4227dba5c7c02f4f476551
font_01_sfnt_off000107ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107AD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011fc4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FC4 11404 bytes
SHA-256: 53c9a168605b7bc16eea6ffc44bfb9039420e5eafbed2d462e7f47be7dfc5c21