Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6d733f2d4789a6e…

MALICIOUS

PDF

80.5 KB Created: 2021-09-15 19:45:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: b98ed5f755391b4119ba310a5d704dcc SHA-1: 989c36567824659567204a9651d729a46c2ab607 SHA-256: f6d733f2d4789a6e172f9fcf301b454e538b7798e8d0f853474ed330d1d35054
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. While no scripts were explicitly extracted, the nature of the URLs and the heuristic firings point towards an attack pattern involving redirection to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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 https://irlanc.ru/uplcv?utm_term=outlook+free+mail+sign+in PDF link annotation
    • https://granitnet.hu/editor_up/wukidal.pdfIn PDF document text
    • http://tccsrl.org/userfiles/files/86681269353.pdfIn PDF document text
    • http://yangs-ns.com/ckfinder/userfiles/files/20210904015734.pdfIn PDF document text
    • http://printific.com/images/contentimages/files/64160640470.pdfIn PDF document text
    • https://zweefvlieg.net/userfiles/file/vuximizurolebubi.pdfIn PDF document text
    • http://scales-center.com/shop/fck_file/file/zenosoponigetozezuwoze.pdfIn PDF document text
    • http://www.puhito.hu/uploads/tapoxaxig.pdfIn PDF document text
    • http://heorungminhphat.com/luutru/files/vividozuzivupajotezubivor.pdfIn PDF document text
    • http://sino-web.net/filespath/files/20210913032016.pdfIn PDF document text
    • http://hairtransplantmangalore.com/uploaded_files/userfiles/files/54743637775.pdfIn PDF document text
    • https://www.soroptimist.be/oldsite/intranet/ckeditor/ckfinder/userfiles/images/files/levovopatitaxefewimute.pdfIn PDF document text
    • https://www.enviedecrire.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136dc7ea68ce---10726045735.pdfIn PDF document text
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/u8iuks1u46eq902pj8o19e5u33/96385383998.pdfIn PDF document text
    • http://cableesmaltado.com/d/files/kotudekoxawimaxorif.pdfIn PDF document text
    • https://www.eecpowerindia.com/codelibrary/ckeditor/ckfinder/userfiles/files/15956830808.pdfIn PDF document text
    • https://nmcs.ca/userfiles/files/28733982566.pdfIn PDF document text
    • http://nusratali.com/userfiles/files/lilejenim.pdfIn PDF document text
    • http://fluorescent-training.com/file/77274660219.pdfIn PDF document text
    • http://obchodsezlatem.cz/upload/files/vigeminerodezoliw.pdfIn PDF document text
    • http://linza-market.ru/upload/files/39866263841.pdfIn PDF document text
    • http://www.tecnotrefg.it/wp-content/plugins/formcraft/file-upload/server/content/files/16138f0bd7aae9---tunusifukupuxidarugu.pdfIn PDF document text
    • https://bohemiamaestro.com/webpagebuilder/ckfinder/userfiles/files/jogesepigumofobika.pdfIn PDF document text
    • https://callmarkinvestments.com/callmark/files/vojevebadelase.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_off0000d529.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD529 17784 bytes
SHA-256: 2b55588d7a75b0a2e9b1b94d2c7ed67248022d59453887efde58e1ea48196c76
font_01_sfnt_off00010368.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10368 10772 bytes
SHA-256: c92a9a688c120bc8dfaa2f0389d88bab7bccc0665ec859e49878eaecf147adb1
font_02_sfnt_off00011c41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C41 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1