Malicious PDF — malware analysis report

Static analysis result for SHA-256 61b4ed2f93f81554…

MALICIOUS

PDF

83.7 KB Created: 2021-09-16 12:13:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c728e7ec1b831f20c07211b9ffcc2b56 SHA-1: c1af15b2400c26e5d5e32364e958a68a5ee5f5aa SHA-256: 61b4ed2f93f81554878b8212927b0ac3fb6b241fb300939013c21b1b2318a171
134 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that are part of a link farm, with many pointing to disposable domains. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. The presence of a 'download' button heuristic further supports a lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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.
  • 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://ff-engineering.com/userfiles/files/92135038191.pdf In PDF document text
    • http://naitikfashions.com/ckfinder/userfiles/files/63739122335.pdfIn PDF document text
    • http://kaiyudachem.com/filespath/files/20210914162511.pdfIn PDF document text
    • http://dalaichau.com/files/44036532942.pdfIn PDF document text
    • http://cwesp.biz/upload/file/65920542535.pdfIn PDF document text
    • http://demo755.webbazaar.com/uploads/giwunetusokikag.pdfIn PDF document text
    • https://www.champagne-auge-dascier.com/ckfinder/userfiles/files/9213569151.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/h0gpbg6u38ndsksfblvreg6c4g/69388644631.pdfIn PDF document text
    • http://ratchadatitan.com/UserFiles/File/torasodirus.pdfIn PDF document text
    • http://bajkolandia-leszno.pl/userfiles/file/53691230560.pdfIn PDF document text
    • http://delve-cr.com/uploads/72994414569.pdfIn PDF document text
    • http://ozdesignhouse.com/app/webroot/uploads/files/nurur.pdfIn PDF document text
    • http://surveycook.com/upload/tmp/202109/file/mabuf.pdfIn PDF document text
    • https://ringid.vn/ckfinder/userfiles/files/58321858582.pdfIn PDF document text
    • http://maryalo.com/userData/board/file/senerulerejapuribomaruf.pdfIn PDF document text
    • https://jin-ji.com/upload/files/fagago.pdfIn PDF document text
    • http://imobilestore.de/userfiles/file/gelewiku.pdfIn PDF document text
    • http://timnhanhonline.vn/upload/files/31018165339.pdfIn PDF document text
    • http://abwalabamaave.com/uploads/files/gifusikiw.pdfIn PDF document text
    • http://energcomb.net/cms_enercomb/sgi_userfiles/userfiles/files/difesadoxuwinowapet.pdfIn PDF document text
    • http://www.bosingels.nl/ckfinder/userfiles/files/bepanusurutun.pdfIn PDF document text
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/1613ae2c8bc772---90362272583.pdfIn PDF document text
    • http://donleroy.net/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/90988170154.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=krack+telugu+full+movie+online+watch+freePDF 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_off0000e129.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE129 18016 bytes
SHA-256: 9ecb4dc80b86516ec2ebfbc4518d528eddf71ecba9e595f970ad4c546a6d4920
font_01_sfnt_off00010fc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FC8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000127df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127DF 10952 bytes
SHA-256: 3c033771865eb26b1e680216cf725a3d281eaf8fcdfc6afcab2a736460f61aa4