Malicious PDF — malware analysis report

Static analysis result for SHA-256 de8be3d7e47847b2…

MALICIOUS

PDF

89.2 KB Created: 2021-09-23 03:45:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 7ec31623e4e56a6851e185475337c130 SHA-1: 2d0daea5d390de6dbb7e094f2a8bb63c455200ab SHA-256: de8be3d7e47847b2e3fd8e8f5e1401a22b0b648832190dfef955cb7df58b0435
134 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and a machine learning classifier, indicating a high likelihood of malicious intent. The presence of embedded JavaScript and multiple external URIs suggests the PDF is designed to redirect users to potentially harmful websites, likely for phishing or to download further malicious content. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports the idea that the PDF is part of a campaign to distribute malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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=thematic+analysis+in+qualitative+research+example+pdf PDF link annotation
    • http://mariopresto.pl/userfiles/file/fipazugezapisinebusulej.pdfIn PDF document text
    • http://25630638.kad.tw/kads/ckfinder/userfiles/files/xukuxizasusuvunomanekawo.pdfIn PDF document text
    • https://chinatupai.com/web/js/ckfinder/userfiles/files/67800752600.pdfIn PDF document text
    • https://kiaavcilar.com/upload/ckfinder/files/64558357897.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613169fdd2ee9---gatuputofenajirusemo.pdfIn PDF document text
    • http://thainightjob.com/ckfinder/userfiles/files/42624400438.pdfIn PDF document text
    • http://3sdent.com/upload/files/wanizutofo.pdfIn PDF document text
    • http://ieeepes-thailand.org/app/webroot/files/files/76842156678.pdfIn PDF document text
    • https://gplacestracker.com/userfiles/file/wetinov.pdfIn PDF document text
    • http://skidubravy.sk/spravca/ckfinder/userfiles/files/38589479155.pdfIn PDF document text
    • http://cartopack.be/Images/file/kujunabe.pdfIn PDF document text
    • https://sportsslife.net/upload/ckfinder/files/xutox.pdfIn PDF document text
    • https://resortweeks.pro/userfiles/file/57777744747.pdfIn PDF document text
    • http://baraanduliaptti.org/userfiles/file/62363031950.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161403b985ee20---zovujajobogoxijewef.pdfIn PDF document text
    • http://jhdjt.com/images/upload/File/reforote.pdfIn PDF document text
    • http://kipia-nn.ru/userfiles/file/79579795262.pdfIn PDF document text
    • https://noithatkuongthinh.com/uploads/files/18221122414.pdfIn PDF document text
    • http://dongamold.com/fckeditor/upload_files/file/73228126688.pdfIn PDF document text
    • http://ivankrivanek.com/userfiles/file/desal.pdfIn PDF document text
    • http://salocchi.it/userfiles/files/95526720576.pdfIn PDF document text
    • https://polymadeniyaglar.com/fckeditor/userfiles/file/jasebejopelap.pdfIn PDF document text
    • http://mpwlawpa.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/27022171287.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_off0000f579.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF579 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010d8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D8B 18200 bytes
SHA-256: a8632a30326f5a07abe57fa310bb77a9e2b52ccc078e143c0028a7572d10cb7c
font_02_sfnt_off00013d10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D10 11256 bytes
SHA-256: 9355e80ef6978f1a1560d6fbf558a1faa3cbe9d5b72a45a6991fab95275bf47e