Malicious PDF — malware analysis report

Static analysis result for SHA-256 85963fb2889a7897…

MALICIOUS

PDF

80.6 KB Created: 2021-06-25 15:19:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: e706f288b8e6b665a8b108b48d4cfcd3 SHA-1: 1e6d87284f6c9823ce07a44c31ec3d640530cf36 SHA-256: 85963fb2889a7897e7c2371226225bca468383205f6ca19d75c911e1061b2604
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple compromised websites, likely intended to host malicious content or phishing pages. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and numerous external links suggest it's designed to redirect users to malicious destinations, potentially as part of a phishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://huntic.ru/uplcv?utm_term=speech+therapy+for+global+aphasia PDF link annotation
    • http://techbis.pl/files/file/7850712776.pdfIn PDF document text
    • https://guapa2.com/admin/fck/file/pulamaberuba.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609a1d3da9609---47600363686.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/e58pposbtd4fiedmejd1pgf8bo/fabefipu.pdfIn PDF document text
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/160702cf40ca1e---14799143228.pdfIn PDF document text
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/7108b48398b5f28dec4bd91e851b1d75/geweduxemigol.pdfIn PDF document text
    • https://medtek.vn/storage/file/48243795090.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/16076bd49ed703---42992405399.pdfIn PDF document text
    • http://julieesteban.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8f01f8bc26---xurilepenalaf.pdfIn PDF document text
    • http://bestbelly.org/content/files/files/bowobenek.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e9aa4ae104---63252350801.pdfIn PDF document text
    • http://bukharaalpharetta.com/sites/default/files/file/22235439140.pdfIn PDF document text
    • http://www.brennholz-heinlein.de/wp-content/plugins/formcraft/file-upload/server/content/files/16077091b4f795---34739631365.pdfIn PDF document text
    • http://tulsamemorialclassof71.com/clients/84987/File/jisoxebax.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/a07e5dff9660884f6a7735ebc1b8de1a/69825027855.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_off0000d791.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD791 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000efa8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFA8 10984 bytes
SHA-256: dfdb0aa074a2d0427d864f3a8b0393db4d07e8cbdd09d70ebb9443b214ccd097
font_02_sfnt_off00010916.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10916 16960 bytes
SHA-256: 507f74c0b4cccb8e8147af62d163b6f07747fb07400947c8196b886deeb0db9b