Malicious PDF — malware analysis report

Static analysis result for SHA-256 553c2acfdd9611ec…

MALICIOUS

PDF

142.0 KB Created: 2021-07-20 07:51:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: b685ae927037395ea99e39ce7adf3ca7 SHA-1: ae78b770a4291d57f941edb0a10211be34128b94 SHA-256: 553c2acfdd9611ec5ddb3b010440e6912a3233a75bffa42f4f658d80f82cb344
156 Risk Score

Malware Insights

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

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous links to compromised WordPress upload storage and disposable hosting, suggesting it functions as a link farm to redirect users to malicious sites. The PDF's structure and the presence of multiple external URIs point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://opuspoint.com/ckfinder/userfiles/files/marenupojojotonodegagekok.pdf In PDF document text
    • http://manixcnc.com/ckupload/files/54467390968.pdfIn PDF document text
    • http://clinicacomciencia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c73de47c4e5---82107872615.pdfIn PDF document text
    • http://armanetti.com/images/vefidizobidebetobikiw.pdfIn PDF document text
    • http://aryajob.com/user_upload/file/jazesedisolalugakidemes.pdfIn PDF document text
    • http://franzoesischebulldoggen.eu/userfiles/file/24095588250.pdfIn PDF document text
    • http://palyavalaszto.hu/teszt/upload/file/34694094936.pdfIn PDF document text
    • http://cameronhaddock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5de233c5a1---furejubexa.pdfIn PDF document text
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a5ffb961cd7---nuleris.pdfIn PDF document text
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/dqlfma82il4ki70ikf1mohvv36/ludori.pdfIn PDF document text
    • https://footballsod.com/images/ck-uploads/files/13007124196.pdfIn PDF document text
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609005bd44062---42323795887.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/loo4t59u99tasr9l1epra90dn6/26672762831.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/49odupvmed18h2cksjq4jc91gr/64887988301.pdfIn PDF document text
    • https://moveo-sport.pl/userfiles/file/43480324755.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/da82020397ba5e5ed750e398b953d6d0/parunixumaxewesevopopi.pdfIn PDF document text
    • http://thcsnguyenvanhuyen.hoaiduc.edu.vn/ckfinder/userfiles/files/lasunufotevogojum.pdfIn PDF document text
    • https://africanresearchcenter.com/userfiles/file/sunopuk.pdfIn PDF document text
    • http://www.scmphotography.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160e4b35ec88b8---nowopiwa.pdfIn PDF document text
    • http://iaestedresden.de/userfiles/file/73996176403.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1e8619b4fa---10489561272.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/160f0827f538d4---bisewesubafejagofaguj.pdfIn PDF document text
    • https://www.tyrtaios.gr/ckfinder/userfiles/files/xekosozopuwagojasev.pdfIn PDF document text
    • http://beamstraffic.ae/amb/userfiles/file/kivajigizomekiwesavi.pdfIn PDF document text
    • https://nguyenvanhuongloc.vn/app/webroot/files/images/pages/files/xomirusupinuzimapugisewo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=middle+school+2+moviePDF 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_off0001ca5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1CA5A 10352 bytes
SHA-256: 6f0334f21be7b350c3b5cdab87f254617890fc51a99dc6342c44261334ccd5e0
font_01_sfnt_off0001e1ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1E1BA 18472 bytes
SHA-256: c1a6b475b148aa3117a34372de30140bde68baef82ab09751335e091fa14a32b
font_02_sfnt_off0002121a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2121A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1