Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3bda80aa15c13c4…

MALICIOUS

PDF

90.1 KB Created: 2021-09-21 03:04:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 02290303913678706067df033539d2e9 SHA-1: 757797a320c12c10880aef33e6ad60cf1d68bdc6 SHA-256: a3bda80aa15c13c4cc53f94108e33e8fa5f1fb552a30cec538254d94aada00f0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL heuristics and malware detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://archism.ru/uplcv?utm_term=s20+fe+vs+iphone+xs PDF link annotation
    • http://home-plast.ru/foto/files/27692304930.pdfIn PDF document text
    • https://tekartltd.com/upload/files/wupedogoxisijawadigo.pdfIn PDF document text
    • http://bctlorraine.org/userfiles/file/36929256061.pdfIn PDF document text
    • http://youil.org/userData/board/file/sited.pdfIn PDF document text
    • http://njuhome.pl/ckfinder/userfiles/files/xolofosixavuluzozozuv.pdfIn PDF document text
    • http://laserinnsbruck.com/static/81129858444.pdfIn PDF document text
    • http://vuatoyen.com/uploads/userfiles/file/87601561479.pdfIn PDF document text
    • https://baust.edu.bd/app/webroot/ckfinder/userfiles/files/doxifus.pdfIn PDF document text
    • http://thoitranglani.com/upload/files/45798998558.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/161461c2331354---gelexab.pdfIn PDF document text
    • http://shippingengineering.com/files/ckeditorothers/sopivugonobuwinebewetube.pdfIn PDF document text
    • https://parquesanalbertohurtado.cl/ckfinder/userfiles/files/4456547968.pdfIn PDF document text
    • https://www.paseppe.gr/ckfinder/userfiles/files/vafobif.pdfIn PDF document text
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/lrhgiojtsannl3dms8tcdnmgr6/41879770151.pdfIn PDF document text
    • http://avvolodin.ru/upload/file/sajufejinirupog.pdfIn PDF document text
    • http://longchimvac.net/app/webroot/uploads/files/libifopivila.pdfIn PDF document text
    • http://peterpan1996.it/userfiles/files/zakuvavutitipiliwojo.pdfIn PDF document text
    • https://ewms.vn/wp-content/plugins/super-forms/uploads/php/files/k16jkaes09tp8ts5oaqoqopunb/56737748936.pdfIn PDF document text
    • https://gitedu.in/ckfinder/userfiles/files/18674122550.pdfIn PDF document text
    • https://dakotaterritorydevelopment.com/ckfinder/userfiles/files/38153738818.pdfIn PDF document text
    • http://computer-rudolstadt.de/upload/file/56890437750.pdfIn PDF document text
    • https://webrobogo.hu/kepek/80554663175.pdfIn PDF document text
    • http://it-hair.com/userfiles/sejufipugu.pdfIn PDF document text
    • 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_off0000fb40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB40 10532 bytes
SHA-256: 1a489e35c682d78174358a391e37b9d4d1ca0372742c4fbcc4820177c1a4f372
font_01_sfnt_off00011338.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11338 18020 bytes
SHA-256: 3936df79a5b65ba0447ec54eeaf9ac5b287984c9736386f73cbc2392912f8611
font_02_sfnt_off000142c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x142C6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1