Malicious PDF — malware analysis report

Static analysis result for SHA-256 d9c4718cc7a979db…

MALICIOUS

PDF

85.9 KB Created: 2021-09-19 04:49:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 13167d5ac7d899168dd6a15a22f2eaca SHA-1: 4fb9f9da3db0caee7f3143634c439b2364b58bb3 SHA-256: d9c4718cc7a979db302e7e204138b68d5adfec5ef354f4fa1d97758a8a320ad6
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, with heuristics indicating it functions as a link farm on disposable hosting. The presence of numerous embedded URLs, many pointing to PDF files on unknown domains, suggests an attempt to redirect users to malicious content or phishing sites. The 'SE_DOWNLOAD_BUTTON' heuristic further supports a lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 6

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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 http://gptools.net/userfiles/file/62498993056.pdf In PDF document text
    • http://cobmedia.hu/include/95864754543.pdfIn PDF document text
    • https://www.alugutader.fr/ckfinder/userfiles/files/pimoka.pdfIn PDF document text
    • https://przygodanaukrainie.pl/admin/ckfinder/userfiles/files/telabetewitoweferilegid.pdfIn PDF document text
    • https://27061010.com/uploads/files/202109181905238762.pdfIn PDF document text
    • https://tectrongim.com/uploads/file/29363424830.pdfIn PDF document text
    • http://sudeoksa.org/userfiles/file/20210919085148.pdfIn PDF document text
    • https://ebal.ro/app/webroot/files/userfiles/files/tekafokewo.pdfIn PDF document text
    • https://techson-cctv.com/upload/file/nezinokafidakiret.pdfIn PDF document text
    • http://polskienarty.pl/data/aktualnosci_imgs/file/22359398170.pdfIn PDF document text
    • http://vouchertiket.com/airplane/ckeditor/uploads/files/58276824518.pdfIn PDF document text
    • http://triatlonbizuterie.cz/sites/default/files/file/35962748329.pdfIn PDF document text
    • https://gentrilieu.vn/userfiles/file/bipeluvuvapitinipuverute.pdfIn PDF document text
    • https://pierrelemagicien.com/userfiles/file/84021985940.pdfIn PDF document text
    • http://demenagements-remond.fr/userfiles/file/20210912003736.pdfIn PDF document text
    • http://gewidor-gmbh.de/uploads/files/dibagugij.pdfIn PDF document text
    • http://tidomusica.com/uploads/files/202109031142445824.pdfIn PDF document text
    • http://vimbark.sk/editor_uploads/files/7045791245.pdfIn PDF document text
    • http://sipzip.com/userfiles/file/11822864130.pdfIn PDF document text
    • http://bjjiffy.com/upload/37439743078.pdfIn PDF document text
    • https://bartonsteel.com/tony/barton/ckfinder/userfiles/files/numapugevifitibejixiliras.pdfIn PDF document text
    • https://websbag.com/uploads/files/gamixosisigowemidagek.pdfIn PDF document text
    • https://mobspace.xyz/web/img/podborky/files/11748426666.pdfIn PDF document text
    • http://eamenfaraz.com/cache/fck_files/file/84379796090.pdfIn PDF document text
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16145d4ea1ba10---tusujemolafesepokisosobi.pdfIn PDF document text
    • http://bahtiyardishekimi.com/fckfiles/file/40277776250.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=amazon+prime+shopping+mod+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_off0000e922.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE922 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010134.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10134 18568 bytes
SHA-256: b14f33413e6e07216d3870ec95282159d45dfcbdcbfc617c9ff41e1b00ceaf20
font_02_sfnt_off00013125.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13125 10828 bytes
SHA-256: 254b05cb5e2913cdf508080b46851f24448b6ca08fed653ae3ca6af69ccb7f0b