Malicious PDF — malware analysis report

Static analysis result for SHA-256 e77b5831f6c7548c…

MALICIOUS

PDF

76.0 KB Created: 2021-10-08 00:21:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: fa35ffdbaad6c374feb6dcf49a52b5d9 SHA-1: 6ef1533f8b67156bec1913dce49797acba89fa16 SHA-256: e77b5831f6c7548c87fe5a9ffbc78d3bb56d27ccc7a7ee090a11f8cd7a05bade
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to redirect users to malicious content. The presence of multiple links to compromised CMS uploads suggests an attempt to host malicious files or redirect to phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

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://drafthe.ru/uplcv?utm_term=cherry+cheesecake+pie+with+condensed+milk PDF link annotation
    • http://aasghsflqsae.handylover.com/upload/files/89042135615.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614f502596c13---7270217288.pdfIn PDF document text
    • https://castilloexterior.es/ckfinder/userfiles/files/kexuralijapixolezetesi.pdfIn PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/99ebadfa20a66b2fc7253744e8be33aa/fopineduwiwivabeworuj.pdfIn PDF document text
    • http://qianshunqs.com/admin/upload/35155225337.pdfIn PDF document text
    • http://hooleihomes.com/cms_images/file/fubijawanomidamibe.pdfIn PDF document text
    • http://anoh.net/pds/userfiles/files/17920570321.pdfIn PDF document text
    • http://okvin.org/userfiles/file/wewidafepovomopido.pdfIn PDF document text
    • http://uptownherndon.com/uploads/files/fafatizusebunasabikifenit.pdfIn PDF document text
    • http://farmaciafoglia.eu/userfiles/files/71722577975.pdfIn PDF document text
    • http://chaitraglaze.com/uploads/82004914116.pdfIn PDF document text
    • http://am-assets.com/aom/magnolia/userfiles/file/82152241675.pdfIn PDF document text
    • http://tsnpharma.com/upload/files/95089297287.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/e57c77d07586ff15e16456316733fc2e/14909248202.pdfIn PDF document text
    • http://rurisnet.org/images/file/36235269627.pdfIn PDF document text
    • http://webcertain.ca/contentupload/fckeditorUploads/organization_/file/fujegudesebi.pdfIn PDF document text
    • http://refah4ter.info/basefile/hotelrefah4terir/files/47783069345.pdfIn PDF document text
    • http://noticiascgnews.com.br/ckfinder/userfiles/files/lijolewapilonixomuro.pdfIn PDF document text
    • http://kangmeideyiliao.com/uploadfile/file///2021100102444261.pdfIn PDF document text
    • http://ekstelekom.com/userfiles/file/91116259283.pdfIn PDF document text
    • https://shiksha24.com/userfiles/files/zozofazorif.pdfIn PDF document text
    • http://thebeautyofdesign.nl/ckfinder/userfiles/files/luloxasisowawevu.pdfIn PDF document text
    • http://gpp300.fr/userfiles/file/kukase.pdfIn PDF document text
    • http://markaz-e-durood.com/EditorImages/file/kekekupibosuduvibide.pdfIn PDF document text
    • http://datacomsystems.cz/userfiles/file/tumosixijoginuvukoxalibe.pdfIn PDF document text
    • http://grafichesirio.com/userfiles/files/kikoxisubopebonabajisil.pdfIn PDF document text
    • https://eagleegg5k.com/ckfinder/triplebuserfiles/file/41214572462.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_off0000c642.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC642 11104 bytes
SHA-256: c85c646a44e2737ac1802c26cbab3e2047c2d24edbbf97a6bdb5d9f90b8233d2
font_01_sfnt_off0000e011.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE011 16560 bytes
SHA-256: 472a8fef0a87b73aaa6b21a83e2135bc1b45c62d7e7d322741898646b5c45a58
font_02_sfnt_off00010a42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A42 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1