Malicious PDF — malware analysis report

Static analysis result for SHA-256 fa21a4c1c739ac47…

MALICIOUS

PDF

80.4 KB Created: 2021-09-09 03:48:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 1b9af6778adec1c344e4e7ea4eaa612e SHA-1: c9c7ebb592722308380726ab2c71a4b814a88f7a SHA-256: fa21a4c1c739ac47d099316bbd3d7a83e0c3e6e79b6f459d4d71da2d7e57494d
134 Risk Score

Malware Insights

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

The PDF contains numerous external URLs, many of which are hosted on domains that appear to be part of a link farm, suggesting a phishing or malware distribution scheme. The ClamAV detection and ML classifier strongly indicate malicious intent, likely to trick users into downloading a secondary payload via the embedded links. The heuristic 'SE_DOWNLOAD_BUTTON' further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://coretry.ru/uplcv?utm_term=organic+synthesis+book+by+jagdamba+singh+pdf PDF link annotation
    • http://peaceinsrilanka.lk/ckfinder/userfiles/files/66738757251.pdfIn PDF document text
    • http://theprojectmanagement.guru/cote_dor_import/admin/ckfinder/userfiles/files/lokujudaxegebamik.pdfIn PDF document text
    • http://currycornersugarland.com/admin/images/file/96010311003.pdfIn PDF document text
    • https://transport-vehicules.fr/userfiles/file/31481160496.pdfIn PDF document text
    • http://ducthanggroup.com/webroot/img/files/jububetolopeze.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/ruvesituwuni.pdfIn PDF document text
    • https://perfumes.dropship-tracking.com/userfiles/files/53582267621.pdfIn PDF document text
    • http://newabel.com/ckfinder/userfiles/files/5044256136.pdfIn PDF document text
    • http://okvin.org/userfiles/file/25429809037.pdfIn PDF document text
    • https://peisheng.org/uploads/ckfiles/files/613513ad80b10.pdfIn PDF document text
    • http://sistarelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/39457873877.pdfIn PDF document text
    • http://smart.sut.ac.th/tsme/src/lib/ckfinder/userfiles/files/bafam.pdfIn PDF document text
    • http://ekachaiguitarist.com/ckfinder/userfiles/files/90847735552.pdfIn PDF document text
    • http://ongxoanhdpe.vn/upload/files/fivumomuzefaximawuruzuned.pdfIn PDF document text
    • http://majortaylorride.info/images/uploaded/file/batijumatobowijamaxotodep.pdfIn PDF document text
    • http://ophtalmic-overnight.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1612efc0d15cb9---bivebas.pdfIn PDF document text
    • http://usairsprings.com/userfiles/file/jenexe.pdfIn PDF document text
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/ecd6fe7d623ba6eccd9e5e3f48c118e7/25329700447.pdfIn PDF document text
    • https://rockyhotelsgroup.com/uploaded/files/nixotijiponemupad.pdfIn PDF document text
    • https://planet-pvc.com/upload/files/61499937868.pdfIn PDF document text
    • https://fasaac.org/temp/files/66571789713.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/28074198198.pdfIn PDF document text
    • http://essentielles-theater.de/UserFiles/File/dinapomisazirozeba.pdfIn PDF document text
    • https://betsin.org/userfiles/files/13149644768.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_off0000d088.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD088 18408 bytes
SHA-256: b5f8cb5106d2495a4a3dfed03ad28ac1ec8b2101cef7c114850ff160861a95aa
font_01_sfnt_off00010105.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10105 11524 bytes
SHA-256: e93daa81845d1b26774f1279a6409adcc3ae5c418e08d112f14d040c4cc635c6
font_02_sfnt_off00011bc9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BC9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1