Malicious PDF — malware analysis report

Static analysis result for SHA-256 23c96c151a1bb519…

MALICIOUS

PDF

83.4 KB Created: 2021-06-14 02:47:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: cd94fa2d999c27ab15515bebe70c028b SHA-1: 1a86000c69f73cceb955e7fa21264706f6b9121b SHA-256: 23c96c151a1bb519af08630df99f2642bf28515e93f373567b0677815e2329ba
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm with numerous URLs pointing to compromised WordPress sites and other domains, suggesting a tactic to distribute malicious content or manipulate search engine results. The ML classifier strongly indicated maliciousness, and the presence of external URIs and a download button lure further support a malicious intent. No scripts were extracted, limiting the analysis of direct execution capabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://coretry.ru/uplcv?utm_term=sub4sub+mod+apk+unlimited+coins+2020 PDF link annotation
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c90c97ed22---66741780439.pdfIn PDF document text
    • https://accesoriosalmayor.com/images/userfiles/file/32175074814.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6830b84b70---66803035675.pdfIn PDF document text
    • https://www.lightingsolutionsinc.net/wp-content/plugins/super-forms/uploads/php/files/3c4b613a1cb477f722a69803f9962f5b/8690770698.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/15627624574.pdfIn PDF document text
    • http://rollfactorytogo.com/uploads/files/notofumerinoneti.pdfIn PDF document text
    • https://agribusiness.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1608e304884b4a---xewuxejujazutenol.pdfIn PDF document text
    • http://lbs.ac.at/wp-content/plugins/super-forms/uploads/php/files/1jde3o0cpnid2gicli47nvcs9n/74537080658.pdfIn PDF document text
    • https://kassa-evotor.ru/wp-content/plugins/super-forms/uploads/php/files/hkeottbek7fctcudhri21mq2qi/sosugatanenisawo.pdfIn PDF document text
    • http://www.ellisrasbetonwerke.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a677136a163---90053232968.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160707f9549f57---xivurosafilujuge.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/ea47d21aa8b15b90c87d3cefed58675e/23211741356.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/c29b3f1f14faf4a37ade24f8fb93da72/31800951662.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e42d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE42D 5792 bytes
SHA-256: 65ac0eb289d6bd3770deaacf705eab1428e2c7a840aa6abf725b580eae7d9a64
font_01_sfnt_off0000f7cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7CB 3160 bytes
SHA-256: ff9de3a950675e72915224bd0643431e41c9780c8a16d6de1c733ea594a4a860
font_02_sfnt_off000104f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104F3 11016 bytes
SHA-256: 3387315c4360ab4b08ff39dfe7c9e26a451f214ad056b76c20f6f050fa31c117
font_03_sfnt_off00012af1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AF1 16096 bytes
SHA-256: da9784c099e5a8bc41ab28ab6b0f706bbb561d129e983fef757841920625d5e7