Malicious PDF — malware analysis report

Static analysis result for SHA-256 1a0d78fe1ce05c23…

MALICIOUS

PDF

69.8 KB Created: 2021-09-25 23:09:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1ce8493bfb5c8babca973c1a95a28cab SHA-1: a7311f357f4bf95815f205901c462b76a981d028 SHA-256: 1a0d78fe1ce05c23014c556d56702d8df85fafe10b37929ba44fa62ffb42f98a
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised or disposable domains, suggesting a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the nature of the links and the PDF structure suggest it may exploit PDF vulnerabilities or serve as a lure for further malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://4bx.pl/public/file/sutamisekegiwup.pdf
    • http://es-manzokudou.com/yamituki-n/uploads/files/kusepevakapobasebe.pdf
    • https://dermatologie-chamonix.com/userfiles/file/gezejutofi.pdf
    • http://vet-arrighicolangelicristilli.eu/userfiles/files/fimapanavuzifek.pdf
    • http://familiegravesen.dk/userfiles/file/xasajizibidudemoraxilakiw.pdf
    • http://cupta.org/userfiles/files/20210919175455.pdf
    • https://hotelexpert.ro/uploads/files/fugulijidavugu.pdf
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/a806081a0d3489bb72220d3d748a6344/37122306856.pdf
    • http://henca.com/files/details/file/moxukete.pdf
    • http://csc-021.com/userfiles/file/20210909072752_075nil.pdf
    • http://sandsflooring.co.uk/ckfinder/userfiles/files/19774473700.pdf
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/8747d29fafd8952aefe6f2ce291ec5de/52535757421.pdf
    • http://gianphoiduyloimodel.com/Images_upload/files/tafopokuvufovedumisab.pdf
    • https://clubkdo.fr/img/pics/files/33894620796.pdf
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/95253654d033274f2b987f1e51508bf6/97460279347.pdf
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/161455a8639241---wegajisev.pdf
    • http://revistaspontan.ro/assets/ckfinder/core/connector/php/uploads/files/jejosolutorubuv.pdf
    • http://hoinhikhoavn.com/img/files/6613947674.pdf
    • http://axwelindia.com/uploads/87752388429.pdf
    • http://skrabl.pl/www/rpbd/fck/file/joxeteni.pdf
    • http://hk-keber.de/images/file/3105269574.pdf
    • https://windscrm.net/files/file/21824016918.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=how+to+see+private+account+photos
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b1d9.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB1D9 16792 bytes
font_01_sfnt_off0000c9eb.bin
39f3abca9a949fa8dbda1535faddb0c9901a2bc733b1e2005d043e8c547ccfd7
pdf-font-stream PDF embedded font (sfnt) at offset 0xC9EB 15616 bytes
font_02_sfnt_off0000f10d.bin
5bcc95fa4ba0ef29c81a96bb7b727953ac03e4ea52b06a5f6b4333a087e911dc
pdf-font-stream PDF embedded font (sfnt) at offset 0xF10D 10668 bytes