Malicious PDF — malware analysis report

Static analysis result for SHA-256 914860f841720e7a…

MALICIOUS

PDF

85.8 KB Created: 2021-09-13 02:17:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 8975a1f51488eba8f4cd795fc60869e3 SHA-1: 14c894e3264fc2cbf7c910d526cf85dc959b2a08 SHA-256: 914860f841720e7adcc37df8bb5dd379d40944d351afe893466b346de7cae0d7
126 Risk Score

Malware Insights

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

The PDF document was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous embedded URLs, including one pointing to 'ketchas.ru', suggests a phishing or malware distribution scheme. The document body, though heavily obfuscated, originates from wkhtmltopdf, a tool often used to generate PDFs from web content, further supporting the idea that the embedded links are the primary malicious component.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 https://ketchas.ru/uplcv?utm_term=friends+watch+online+free+with+english+subtitles PDF link annotation
    • http://deaprogettazioni.it/userfiles/files/25620384966.pdfIn PDF document text
    • http://lmalaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/11806338497.pdfIn PDF document text
    • http://stringquartet.biz/web/images/fck/file/texagimuz.pdfIn PDF document text
    • http://swiss-ex.com/images/blog/file/nudijesapedelipujatitajum.pdfIn PDF document text
    • https://shibbirs.com/media/files/novakidetupisox.pdfIn PDF document text
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/fd4c1043412f7e02260a60dbb7bc2447/dopafidopezamagazezoremur.pdfIn PDF document text
    • http://gaestehaus-am-erlkoenig.de/img/editor/file/18993693006.pdfIn PDF document text
    • https://milosislandrooms.gr/userfiles/file/24478437161.pdfIn PDF document text
    • https://malabarmail.com/ckfinder/userfiles/files/90219477094.pdfIn PDF document text
    • https://zaindu.drogomedia.com/files/galeria/files/87286498883.pdfIn PDF document text
    • http://www.lbf-cosmetics.com/website/wp-content/plugins/formcraft/file-upload/server/content/files/16139414beb6ce---69247321677.pdfIn PDF document text
    • https://salvamontbihor.ro/app/webroot/files/userfiles/files/bizuf.pdfIn PDF document text
    • http://scenekunstskolen-efteruddannelsen.dk/ckfinder/userfiles/files/posedidipagisosofoxi.pdfIn PDF document text
    • http://edwindijk.nl/home/edijk/domains/edwindijk.nl/public_html/uploads/file/41585548349.pdfIn PDF document text
    • https://impulsa.mantareys.net/uploads/plantillas/files/50979471513.pdfIn PDF document text
    • https://aathichudi.org/userfiles/file/xuduka.pdfIn PDF document text
    • https://giraffeng.net/infodaily/gen-ckfinder/userfiles/files/bozigitulowagulik.pdfIn PDF document text
    • https://cakkue.com/contents/files/mexuzokezewon.pdfIn PDF document text
    • http://pro-roubenky.cz/UserFiles/File/wesomibutusubowurumitino.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/60011221449.pdfIn PDF document text
    • http://gemculture.com/userfiles/file/fajejemezovoxeti.pdfIn PDF document text
    • http://bangkokmagnetwire.com/ecodev_test/image_system/files/buzilon.pdfIn PDF document text
    • http://bigcool.net/webroot/img/files/tofiwaxukazukowuxoxixajiz.pdfIn PDF document text
    • http://anninh247.info/upload/files/fisetanojolekexitusorite.pdfIn PDF document text
    • http://6nergy.fr/6nergy/sites/default/user/file/35569951612.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_off0000e27c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE27C 11060 bytes
SHA-256: d02c78420d32a913b6e8b14589ab7dd8773b5ab55b90eeda0d96eb7f44462ceb
font_01_sfnt_off0000fc05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC05 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011417.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11417 20420 bytes
SHA-256: cc36f5ef1df3906b4dc5c7706dce1f7e3589db70d2c0680ce6091974319ddfb5