Malicious PDF — malware analysis report

Static analysis result for SHA-256 c838d2ec9618c2b3…

MALICIOUS

PDF

75.2 KB Created: 2021-10-04 02:54:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: dd6e5808c080af5afc8fc7d1cf1becbd SHA-1: 0fec2f8d6dac540517cc91b28b0d53c633894c29 SHA-256: c838d2ec9618c2b32eb5c2deac5af4bd142fbe61b7253f8cda8ad0dfedaadd94
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous external URIs, many pointing to disposable hosting and configured as link farms, strongly suggests a phishing or malware distribution campaign. The document body is heavily obfuscated and unreadable, but the overall structure and URL patterns are consistent with a malicious PDF designed to redirect users to harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://synerhu.ru/uplcv?utm_term=economic+guided+reading+answers PDF link annotation
    • https://tapetcenter.ro/app/webroot/files/userfiles/files/kulesipi.pdfIn PDF document text
    • http://youandisagenix.com/ckfinder/userfiles/files/83066360646.pdfIn PDF document text
    • http://balassalaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/64253942163.pdfIn PDF document text
    • https://tpk-m.ru/files/file/ritewajezesavobo.pdfIn PDF document text
    • http://stopguepes72.fr/userfiles/file/59047802606.pdfIn PDF document text
    • http://manuale.aziendasulweb.it/userfiles/files/44378990597.pdfIn PDF document text
    • https://www.dyna-tech.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614beee9c58f1---mafugopilexud.pdfIn PDF document text
    • https://jokerprod.net/userfiles/file/69276446735.pdfIn PDF document text
    • http://selfmadefilms.nl/userfiles/files/5283472840.pdfIn PDF document text
    • http://itnetworkconsultingsf.com/helpdesk/app/webroot/img/userfiles/files/rigafegirulazubimamejesi.pdfIn PDF document text
    • http://infoguard.ru/content/file/98240264478.pdfIn PDF document text
    • http://ruishikaishi.com/upload/content/files/2021/09/20210902200901.pdfIn PDF document text
    • http://telegid.tv/userfiles/file/61448851084.pdfIn PDF document text
    • https://nnt52.ru/userfiles/file/tinatinexupidolediju.pdfIn PDF document text
    • http://natpuedu.in/userfiles/file/kuwewuvug.pdfIn PDF document text
    • http://brandnewgoods.net/userfiles/file/88556207274.pdfIn PDF document text
    • https://baust.edu.bd/app/webroot/ckfinder/userfiles/files/63789569982.pdfIn PDF document text
    • https://hkparkkonutlari.com/image/files/59581034344.pdfIn PDF document text
    • http://adirondackseafood.com/ckfinder/userfiles/files/74397377465.pdfIn PDF document text
    • http://grafittipng.com/userfiles/files/memedikopoguz.pdfIn PDF document text
    • https://partnyor.az/userfiles/file/mimajubavixawelanevesit.pdfIn PDF document text
    • http://korea-labels.com/ckfinder/userfiles/files/nopag.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_off0000bb12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB12 10740 bytes
SHA-256: 28e07b2b17cef214accc2da4f889ca88c13797716959b6635319aaeb4fb652d0
font_01_sfnt_off0000d38f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD38F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eba1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBA1 19776 bytes
SHA-256: c64f15153a2955ecf1522744c7826a78137da4e247bbaaa79ef2b3b726fa1e72

Open this report in the interactive analyzer, or submit your own file for analysis.