Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b5dd382f52a5449…

MALICIOUS

PDF

76.7 KB Created: 2021-04-29 02:34:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 3f76e45b4bd68118705e6ba5d6073391 SHA-1: d6e87132695ca37763a44dad2f419c404a6ceea0 SHA-256: 4b5dd382f52a544951f91167f100f4562c69580bb78b44bd02134507fa55d875
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many hosted on compromised CMS upload directories, suggesting a link farm or phishing lure. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to redirect users to malicious content, likely for malware distribution or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 http://www.mkkdigital.pt/wp-content/plugins/formcraft/file-upload/server/content/files/16083f10150315---wofevalujagavuriworoz.pdf In PDF document text
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/3m54kb60rmgmenp18qoti49171/temebozefudujomofavu.pdfIn PDF document text
    • https://www.sacda.org/wp-content/plugins/super-forms/uploads/php/files/5kn2d3ponr7jombgtrd0e1fi64/zafofodefuxibomozopinonif.pdfIn PDF document text
    • https://pousadamarazul.tur.br/wp-content/plugins/formcraft/file-upload/server/content/files/16085753e942a1---68554549736.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/p12lc71cgfv8kjqkc0aughjjs0/pebixosotujanazelo.pdfIn PDF document text
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/1607a5fa009e8f---xilarudexagoze.pdfIn PDF document text
    • https://www.asahinafunnels.com/wp-content/plugins/super-forms/uploads/php/files/7v88i6hf2m0kjrirocf3nr7fgd/55270629689.pdfIn PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/e35fdaf77e8f885002a86d70c5254ff8/26700762154.pdfIn PDF document text
    • https://travels-ukraine.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084b971573f2---57150652700.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/1608243832e25a---90356205833.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f8dc12c4b4---13687857428.pdfIn PDF document text
    • http://argentum.com/wp-content/plugins/super-forms/uploads/php/files/7oo8bpfn62qu8eoobdbnrs1pkv/25412191332.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085b19857c15---pepuratidawigugebis.pdfIn PDF document text
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/1607db5591ce07---2264328325.pdfIn PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160731a3ea6ec5---56567144246.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086053ccf4ce---xigupokitonosafi.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607296fdcf427---29214767058.pdfIn PDF document text
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/9a7b2ba284c761568aa44ead205c185c/kamuruvemimadiwisubatap.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=annualized+performance+calculation+excelPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000dfb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFB4 5112 bytes
SHA-256: 718788155b1034ff0bf04486570f56bbe2c572ca31802ac7984a9c222f339332
font_01_sfnt_off0000f109.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF109 11100 bytes
SHA-256: a063ca00a58a57bbbfeb1ca25383c289f6615eaef481d27c2ff6da71162a0fa7
font_02_sfnt_off00011715.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11715 4324 bytes
SHA-256: 05d2457133b820fa77aa358e30e9acfbad3f04c46ced9a37296d9311117db176