Malicious PDF — malware analysis report

Static analysis result for SHA-256 4722a9b7030347f0…

MALICIOUS

PDF

79.5 KB Created: 2021-09-09 19:17:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 0cdec9ed80fa081345a052a069f1f676 SHA-1: 44cc2331747fec3a950ef1493f6ff30e24af43b5 SHA-256: 4722a9b7030347f0ca09bdd657f0aabb5e94c781e403ae476dde308dc5fbca3d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, with one heuristic specifically identifying it as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were directly extracted, the PDF structure and embedded links suggest it's designed to lure users to external, potentially malicious, resources.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 http://baldonimarcostudio.eu/userfiles/files/vategab.pdf In PDF document text
    • http://shriramashramssschool.org/userfiles/file/33304464905.pdfIn PDF document text
    • http://www.yeosung21.or.kr/ckfinder/userfiles/files/1631082731.pdfIn PDF document text
    • https://inprovitchile.com/ckfinder/userfiles/files/10022147287.pdfIn PDF document text
    • https://cheeselicious.net/UserFiles/file/72243236431.pdfIn PDF document text
    • http://csc020.com/userfiles/file/20210902122516_y2ugjh.pdfIn PDF document text
    • http://touristclub.in/userfiles/file/ziwifugifer.pdfIn PDF document text
    • https://promptcorporate.com/ckeditor/ckfinder/userfiles/files/80509492901.pdfIn PDF document text
    • http://tensoinox.com/userfiles/files/zejomevoxufu.pdfIn PDF document text
    • https://gotoko.com/cmsv2/upload/files/xibitobe.pdfIn PDF document text
    • http://abnicum.com/files/file/18719018687.pdfIn PDF document text
    • http://bowie.abwingsmd.com/uploads/files/9607102244.pdfIn PDF document text
    • http://sicilyontable.it/userfiles/files/nusajazisatul.pdfIn PDF document text
    • http://erulingua.hu/uploads/content_files/files/ninetibekudawefexuwipubol.pdfIn PDF document text
    • http://geometrabottero.it/userfiles/files/7901949062.pdfIn PDF document text
    • https://turkeyinsurance.info/images/file/gafix.pdfIn PDF document text
    • https://mtestbd.com/assets/uploads/files/45216685206.pdfIn PDF document text
    • http://jts-electrical.co.uk/ckfinder/userfiles/files/simerabibojaleromiduludod.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161328c4fefc19---75665012429.pdfIn PDF document text
    • http://divodizain.ru/ckfinder/userfiles/files/31267599439.pdfIn PDF document text
    • https://pepsima.biz/files/file/fidefetarexe.pdfIn PDF document text
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16135b11cd8f16---56722658796.pdfIn PDF document text
    • http://rentbucharest.net/images/userfiles/nobupo.pdfIn PDF document text
    • https://strategieb2b.ca/userfiles/file/41662804863.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=understanding+the+learner+and+learning+process+pdfPDF 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_off0000d3de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3DE 16712 bytes
SHA-256: cd6da60f3b81d9cd579fe5adfbbd48126d3cd577cd0f7a84f53014beef6983a9
font_01_sfnt_off0000fefb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEFB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011712.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11712 10908 bytes
SHA-256: 771269c2df604c49be743267babd42c1b1bd4a1600a958f8a093d03c6d94506a