Malicious PDF — malware analysis report

Static analysis result for SHA-256 f051496f28709b25…

MALICIOUS

PDF

81.6 KB Created: 2021-09-20 00:06:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: 34e136c81ed8a15f10d9fec001c342ed SHA-1: 85b443d93f607c3ea039d3a6579c6c0dfb2ba5cd SHA-256: f051496f28709b25b4ed45735152ee838937a34e89cbf486356c9732b3027b38
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a high number of external URIs pointing to a link farm hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is heavily obfuscated and unreadable, but the heuristics and URL analysis reveal a pattern of redirecting users to potentially malicious content.

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
  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://777mto.com/contents/files/29206802074.pdf In PDF document text
    • http://cserepakcio.hu/xdata/file/laxuromigalubirekobixa.pdfIn PDF document text
    • http://dubilex.com/userfiles/files/vefamidegovasuxukep.pdfIn PDF document text
    • http://zhizhencn.com/filespath/files/20210910102739.pdfIn PDF document text
    • http://exdebt.bg/userfiles/file/48083720335.pdfIn PDF document text
    • https://www.db-ynox.fr/ckfinder/userfiles/files/26021154443.pdfIn PDF document text
    • http://emanuelarombiarchitetto.eu/userfiles/files/kirizudojewebugirojaz.pdfIn PDF document text
    • http://ekonopuntos.com/campannas/file/15219421852.pdfIn PDF document text
    • http://chochosanencino.com/uploads/files/fevuz.pdfIn PDF document text
    • https://theptaynam.vn/upload/files/zivokowuj.pdfIn PDF document text
    • http://productinfo.in/konadnew/userfiles/file/xakoxexagogusub.pdfIn PDF document text
    • http://congtyvima.com/images/Download/41442716234.pdfIn PDF document text
    • http://farmaciafoglia.eu/userfiles/files/gevadojanamepuwofivaxube.pdfIn PDF document text
    • http://www.jacenter.org/js/ckfinder/userfiles/files/pozusalutow.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/1iv20hl6qdes11qluh6c8gr97c/75097501939.pdfIn PDF document text
    • http://sinproval.it/userfiles/files/fejegitamerivevilij.pdfIn PDF document text
    • http://inoxbienhoa.com/upload/files/46666638984.pdfIn PDF document text
    • http://quincy.pl/ckfinder/userfiles/files/midekijupiban.pdfIn PDF document text
    • http://farmaciacogliate.it/userfiles/files/98942236563.pdfIn PDF document text
    • http://silverk.ru/img/lib/file/vogomi.pdfIn PDF document text
    • http://tokyosushilohaus.com/uploads/files/jodidub.pdfIn PDF document text
    • https://plasy.com/uploads/file/fajilapokibukel.pdfIn PDF document text
    • https://joebalogh.ro/imagini_ws/22347750517.pdfIn PDF document text
    • http://xn--oy2b19v1mb1yi.com/userfiles/file/34183156048.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=contacts+transfer+apkPDF 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_off0000da83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA83 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f295.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF295 18096 bytes
SHA-256: 6f33a2cc1816fef7ce8761086919527cf2da003a9780f666e586eca628681e85
font_02_sfnt_off000120ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120CE 10460 bytes
SHA-256: 259ffb910348f6149be88f1980d84045aba5f65db7272e90e0c37cf5f405e617