Malicious PDF — malware analysis report

Static analysis result for SHA-256 59a89226ca8c1232…

MALICIOUS

PDF

82.8 KB Created: 2021-09-18 19:23:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 450b4f5065a192d364ab0186d0a7c4c9 SHA-1: aa78dbfb0097e01d34923f368b33a2499cf3adb8 SHA-256: 59a89226ca8c1232ae795d08f2c8781002e765d8abd7e91b8a8e7eb3c0e788e2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ClamAV as a phishing trojan and a machine learning classifier indicated a high probability of maliciousness. It contains numerous external URIs and link farm patterns, suggesting it is designed to redirect users to potentially malicious websites. The presence of compromised CMS upload links further supports this, indicating a technique to host malicious content on seemingly legitimate but compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://infrive.ru/uplcv?utm_term=basketball+stars+mod+apk PDF link annotation
    • https://biblioteka-koneck.pl/ckfinder/userfiles/files/geziduvatabipakorozivo.pdfIn PDF document text
    • http://educasters.co/ckfinder/userfiles/files/napawadirunorodofubumen.pdfIn PDF document text
    • https://stepweystudy.com/ckfinder/userfiles/files/1156260114.pdfIn PDF document text
    • http://vitacanes.com/uploads/files/pudixovimasokepex.pdfIn PDF document text
    • http://lyzph.com/userfiles/file/Fl202109050817474254.pdfIn PDF document text
    • http://watchimport.eu/userfiles/file/2369831042.pdfIn PDF document text
    • http://mbjarrahi.com/UploadedFiles/New/file/tulikanavowovulijo.pdfIn PDF document text
    • http://lyzph.com/userfiles/file/Fl202109111247348377.pdfIn PDF document text
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612eaac20bcba---mogowuvetosu.pdfIn PDF document text
    • http://vandervalk.reviews/app/webroot/files/userfiles/files/65613545901.pdfIn PDF document text
    • https://biserica-izvorul-tamaduirii.ro/files/4160752510.pdfIn PDF document text
    • http://rungrawin-itt.com/userfiles/files/xufugeno.pdfIn PDF document text
    • http://qwerty.pl/_data/file/52129642415.pdfIn PDF document text
    • http://szerecsengyogyszertar.hu/editor_up/26834967447.pdfIn PDF document text
    • https://thietbigas.net/media/files/43749879312.pdfIn PDF document text
    • http://seibyou-koujien.com/files/files/zevop.pdfIn PDF document text
    • https://unovosti.tv/ckfinder/userfiles/files/97743351068.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/a19b97858a332769b9e10d0bb1f9741f/gopej.pdfIn PDF document text
    • http://annabarons.lv/files/files/63225748053.pdfIn PDF document text
    • http://bergepkolcsonzo.hu/userfiles/file/zukufa.pdfIn PDF document text
    • https://bushregenerators.net/userfiles/files/vijixanelijijo.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613e8094b6d62---foxumevuxogaxizinilolo.pdfIn PDF document text
    • https://xeroxexpres.cz/userfiles/file/zunafefofusasakof.pdfIn PDF document text
    • http://printific.com/images/contentimages/files/83293411820.pdfIn PDF document text
    • https://apartmani-mestrovic-krk.hr/files/kadirukukavemu.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_off0000df9f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF9F 10640 bytes
SHA-256: cf4ef8272dc2577e9e981fb2719f9643a7e4c65d533670221718194cbcbfc943
font_01_sfnt_off0000f7db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7DB 17440 bytes
SHA-256: d679c22f0a30ae56950f800db7f53a7dcd529967da695ce3dbabd16f60d2096d
font_02_sfnt_off00012567.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12567 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1