Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4aa0fb46d67c163…

MALICIOUS

PDF

71.6 KB Created: 2021-09-24 07:04:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: e5406d12f3166c5664ccf21608f6a548 SHA-1: b762d9c5f478f24e1b5117c2109f7f36c376f2ca SHA-256: c4aa0fb46d67c163dfa2f0f44ece8b3e98fbe1e03cd7617da88f1ce6fadb896a
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and the presence of numerous distinct external PDF links suggest the document's primary purpose is to act as a redirector to potentially malicious content. The embedded URLs, despite some being marked as benign, are part of a larger pattern of link farming.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://tranindo.com/Uploads/userfiles/files/wijizusovusukowajobenafo.pdf In PDF document text
    • http://vom-ragnaroek.de/uploads/file/gowakebusuxolaxenatewebu.pdfIn PDF document text
    • http://etoprosto.ru/ckfinder/userfiles/files/lewedexafetikep.pdfIn PDF document text
    • https://sushixusa.com/userfiles/files/86793037094.pdfIn PDF document text
    • http://sosnovgeo.ru/userfiles/file/27034837540.pdfIn PDF document text
    • https://olivier-daulte.com/ckfinder/userfiles/files/momipureletelokirej.pdfIn PDF document text
    • http://studiomontironi.eu/userfiles/files/72433519080.pdfIn PDF document text
    • https://peperita.it/writable/public/userfiles/file/pifesim.pdfIn PDF document text
    • https://dm288.rs/slicice/file/86504640309.pdfIn PDF document text
    • http://foto-preiss.at/upload_files/files/98514679751.pdfIn PDF document text
    • http://tries.cz/media/images/upload/file/96800381837.pdfIn PDF document text
    • https://j26clean.com/upload/files/72894871025.pdfIn PDF document text
    • http://haenuri.net/ckupload/files/11607967238.pdfIn PDF document text
    • https://aynispirit.nl/userfiles/file/putuj.pdfIn PDF document text
    • http://tincorner.vn/uploads/files/97934332602.pdfIn PDF document text
    • https://kfk-dekoration.dk/images/uploadedimages/file/jowelida.pdfIn PDF document text
    • https://www.campacinter.com/image/upload/File/rigisupegupi.pdfIn PDF document text
    • https://www.pirkitpadangas.lt/ckfinder/userfiles/files/xipivotofazavu.pdfIn PDF document text
    • https://limberhurstgallery.com/imageuploads/file/65299412672.pdfIn PDF document text
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/16144fe170e5f6---7881643116.pdfIn PDF document text
    • http://jubangh.com/Upload/FckUpload/20210924file///19320848435.pdfIn PDF document text
    • http://bbhshipyard.com/userfiles/file/12333837414.pdfIn PDF document text
    • http://aranykoronakft.hu/userfiles/file/benixatudem.pdfIn PDF document text
    • http://homelife-superstars.com/image/files/42934737621.pdfIn PDF document text
    • http://kfnmdg.com/upfolder/e/files/20210904061553.pdfIn PDF document text
    • http://erictex.com/ufiles/files/11084474373.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=watch+tv+everywherePDF 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://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_off0000b8ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB8EE 10056 bytes
SHA-256: eb012fbec79ad16269bcbd11bba422887e12a2e4f6fe72932ab81cf9ca326ac8
font_01_sfnt_off0000cf82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF82 15972 bytes
SHA-256: 164d78acbfd4a5de17538a77b4e4f7b08196b373e6546a30422043cd1de8fbf7
font_02_sfnt_off0000f8a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8A2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1