Malicious PDF — malware analysis report

Static analysis result for SHA-256 a1d18f8be9fe4ab8…

MALICIOUS

PDF

77.8 KB Created: 2021-09-15 13:22:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1c4014d7392a8dd92270bd5aedd86c54 SHA-1: 5040fe75d1d2934d824bbfcad1d3ede702863c3c SHA-256: a1d18f8be9fe4ab83a34e8cb93c1988898104c47cae0935c5c1fffe9c33390f2
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a high number of embedded URLs, many of which point to disposable domains and are used in a link farm pattern, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and numerous external links are indicative of a malicious document, likely leveraging embedded JavaScript for malicious actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 https://krisoc.ru/uplcv?utm_term=algoritmos+de+programacion+pdf
    • https://sanmuabancongty.vn/images/content/files/mufapofazedujowomuj.pdf
    • http://bnblspecialities.com/userfiles/files/fisapewuviminituzazomataz.pdf
    • http://accessibilite-salle-eau.com/ckfinder/userfiles/files/gadarokujupavawew.pdf
    • https://pirkitpadangas.lt/ckfinder/userfiles/files/62293981694.pdf
    • http://candleelectricals.com/uploaded_files/userfiles/files/3611765335.pdf
    • http://acsalma.hu/userfiles/files/89877216998.pdf
    • https://nhuadailoan.vn/upload/userfiles/files/51487738366.pdf
    • https://kominove-centrum.cz/media/files/file/vakezasutubelenuwake.pdf
    • https://kaxtongroup.com/home5/maxconne/public_html/kaxtongroup/assets/images/newspostimages/files/5997525732.pdf
    • http://resurrection-life.net/userfiles/files/wakovorurujulejafana.pdf
    • https://premiumvipbusiness.com/wp-content/plugins/super-forms/uploads/php/files/7ebaacd80d8585e1365893b221f4dff5/rovaxojivi.pdf
    • http://coomargroup.com/ckfinder/userfiles/files/27602963864.pdf
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/4996a6bd9541bf0521323a8c975be62b/belogatibasorigixofinawe.pdf
    • http://korsorlampang.net/user_img/files/fimarafiwajavumam.pdf
    • http://cgpharma.in/cote_dor_import/admin/ckfinder/userfiles/files/25300918099.pdf
    • https://fo-prefectures.com/pages/files/xilesirusifi.pdf
    • http://xn--365-pn7mwb654m2qn.com/ckupload/files/kezigedesaboviw.pdf
    • https://daquin-ferriere.fr/userfiles/file/genanegikokalimaxunane.pdf
    • http://abarappresentanze.it/userfiles/files/80483326613.pdf
    • http://ntouioc.ntou.edu.tw/ckfinder/userfiles/files/kigijag.pdf
    • http://omonetach.pl/foto/ilustracje/file/11911176204.pdf
    • http://bluestandard.pl/ckfinder/userfiles/files/sumeruwaxajatefenevoj.pdf
    • 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_off0000cc75.bin
07c6e8cfad04c13f005185676d415416c3211c8ce813e215ebfaff05352a0205
pdf-font-stream PDF embedded font (sfnt) at offset 0xCC75 10944 bytes
font_01_sfnt_off0000e59c.bin
90d447f51c7468a0e1a1abd8bfe3c9c3b05556fc6e81e30236e6a034f92fcc21
pdf-font-stream PDF embedded font (sfnt) at offset 0xE59C 17376 bytes
font_02_sfnt_off000111b0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x111B0 16792 bytes