Malicious PDF — malware analysis report

Static analysis result for SHA-256 6efd23669b922740…

MALICIOUS

PDF

82.9 KB Created: 2021-09-18 21:04:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: d56248e776dcc7092529590289b7c7bd SHA-1: abb6bc04764252078b05966f1378519fefe2fed9 SHA-256: 6efd23669b92274067dd31689332daa7830d35f8a3819447c00c90ae80e70bc7
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as a phishing trojan. It contains numerous embedded URLs that form a link farm, pointing to various compromised websites and disposable hosting. The presence of embedded JavaScript suggests an attempt to execute malicious code within the PDF viewer, likely to facilitate the redirection to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • 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://archism.ru/uplcv?utm_term=watch+fast+and+furious+9+online PDF link annotation
    • http://zimmerei-possert.at/53476926970.pdfIn PDF document text
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/16145c361f216c---bazedu.pdfIn PDF document text
    • https://chowdhurytourism.com/ckfinder/userfiles/files/zulujifa.pdfIn PDF document text
    • https://iaido-iaijutsu.ru/userfiles_exc/bibezurukedepizisajosoxa.pdfIn PDF document text
    • https://keiba-like.biz/js/ckfinder/userfiles/files/tolidotirozositorulibax.pdfIn PDF document text
    • https://vanvoorst.info/uploaded/file/tixitevunamejetumumunow.pdfIn PDF document text
    • http://floramarble.com/uploads/girejunasesunadidekufaj.pdfIn PDF document text
    • https://anne-berger.de/sites/anne-berger.de/files/fkcfile/2593444688.pdfIn PDF document text
    • http://bronia.org/userfiles/file/tufepukem.pdfIn PDF document text
    • https://rosewoodcity.org/nbloom/fckuploads/file/20698606033.pdfIn PDF document text
    • http://nayyaralidada.com/alpha/ckfinder/userfiles/files/xenafakiwonejopatetupepes.pdfIn PDF document text
    • http://chapelguild.com/images/usr/87355807313.pdfIn PDF document text
    • http://recruiters-zone.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138ef7ff39d4---8002533315.pdfIn PDF document text
    • https://bharatiyabhashaparishad.org/ckfinder/userfiles/files/3184231709.pdfIn PDF document text
    • http://hanyuchina.com/upload/files/54174130120.pdfIn PDF document text
    • https://lifesmart.lifesmart.ro/ckfinder/userfiles/files/bunijozefasu.pdfIn PDF document text
    • http://llux.vn/uploads/files/negane.pdfIn PDF document text
    • http://xn--80aesyq.xn--p1acf/files/file/pugixitowokakoxumobex.pdfIn PDF document text
    • http://abnicum.com/files/file/raviwulorijuvapelo.pdfIn PDF document text
    • http://uslugi-ogrodnicze.pl/pliki/File/6376908047.pdfIn PDF document text
    • http://uitetenindex.nl/images/uploads/4517072013.pdfIn PDF document text
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614313189526b---rawafewaxoxefuvabesobix.pdfIn PDF document text
    • http://slxiang.com/v15/Upload/file/20219152146267030.pdfIn PDF document text
    • https://hkfew.org.hk/ckfinder/userfiles/files/jisegun.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_off0000dcf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCF6 10836 bytes
SHA-256: d4253ef36c2fea02c73178e2d4af11578a3ae5bf1e1474de347469650bba2bbf
font_01_sfnt_off0000f5f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5F9 18240 bytes
SHA-256: aa23f45c493bee62694a009d522733d3c937077d566912ee947864a75372f6bd
font_02_sfnt_off000125bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125BF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1