Malicious PDF — malware analysis report

Static analysis result for SHA-256 55a10e9fe3ec14fd…

MALICIOUS

PDF

78.9 KB Created: 2021-09-11 21:15:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: cadf7c52ee7d3ab4643cd94cd0633753 SHA-1: 69a59b4e46e406cfc5e58f8a69a6951b045172a1 SHA-256: 55a10e9fe3ec14fd99ab019a7a67c413407cc2682d9238be706fb1f20a826eee
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. The presence of numerous links to disposable domains, including one explicitly containing 'utm_term=download', suggests a phishing or malware distribution attempt. The document body, though heavily obfuscated, contains metadata indicating it was generated by wkhtmltopdf, a tool often used to create PDFs from web content, further supporting the idea of a web-based lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://xageunion.com/userfiles/file/32902699378.pdf In PDF document text
    • http://fresh-j.info/images/uploadedimages/file/pugaruje.pdfIn PDF document text
    • https://eminenceconstruction.ca/viking1/uploads/files/kunaxejapaberigob.pdfIn PDF document text
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/metikoronan.pdfIn PDF document text
    • http://sinorarechem.com/upload/files/70115302865.pdfIn PDF document text
    • https://tractorpulling-emmeloord.nl/upload/file/39284441078.pdfIn PDF document text
    • http://phonphangschool.com/upload/files/86641024964.pdfIn PDF document text
    • http://habitat3.eu/userfiles/files/nadurakirezozumukube.pdfIn PDF document text
    • http://erodiertechnik-wenzel.de/userfiles/file/zabodozi.pdfIn PDF document text
    • http://kangshi-you.com/uploads/files/202109032022446626.pdfIn PDF document text
    • http://biogenetec.tw/image/files/20210909_195537.pdfIn PDF document text
    • https://yuanfuconstruction.com/ckfinder/upload/files/bizuramefoji.pdfIn PDF document text
    • http://12shio5.com/contents/files/faropatiraxonomuj.pdfIn PDF document text
    • http://hagelkonzept.de/userfiles/file/20465743622.pdfIn PDF document text
    • https://brianspradlin.com/userfiles/file/35671065736.pdfIn PDF document text
    • http://osteriailgalloelinnamorata.com/userfiles/files/61318155065.pdfIn PDF document text
    • http://www.deco-interieure.com/userfiles/file/madarilin.pdfIn PDF document text
    • https://kiofruits.com/admin/uploads/files/pefaritefekimujovepa.pdfIn PDF document text
    • http://hagelkonzept.de/userfiles/file/bemazapabob.pdfIn PDF document text
    • https://mimpidia.com/contents/files/sevixelakolifarupeb.pdfIn PDF document text
    • https://facades-et-traditions.com/actualites/file/muvanerenolanote.pdfIn PDF document text
    • http://fertilityupdates.com/userfiles/files/devigagamijal.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/161327fc57e942---94736705233.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=download+fanatical+car+driving+simulator+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_off0000ce77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE77 17436 bytes
SHA-256: 6d49050212dc106b1697b419295423f38440dae8d97576a05e6cce0d69558758
font_01_sfnt_off0000fc0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC0C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011423.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11423 11176 bytes
SHA-256: 62b432395aaf4412eff8ddb23b00f9e94125eecedcd1d1f55a3b3adb9c4deac4