Malicious PDF — malware analysis report

Static analysis result for SHA-256 01737fd7842d0792…

MALICIOUS

PDF

87.1 KB Created: 2021-09-19 01:47:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 5fbb9cc4e943c3fe62ffcb4dbdc1a4f4 SHA-1: 80915e7fb7e9bbb1f0a7f845ca8fd9536f75d305 SHA-256: 01737fd7842d0792b6beaf4e2ded7a28258702e2e85b742fcd88a76d85e11568
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to numerous external URLs, many of which are hosted on disposable domains. The presence of embedded URLs and the nature of the heuristics strongly suggest an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • 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.
  • 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://wastran.ru/uplcv?utm_term=catcher+in+the+rye+chapter+1+pdf PDF link annotation
    • http://laibros.com/ckeditor/userfiles/files/87538538976.pdfIn PDF document text
    • https://dcimx.com/files/46624444214.pdfIn PDF document text
    • http://bapassamarinda.id/assets/ckfinder/core/connector/php/uploads/files/15958899494.pdfIn PDF document text
    • http://watch62.ru/files/files/zituwofilugerupejuvik.pdfIn PDF document text
    • https://zemtechnika.lt/public/site/0files/viwupisukotumivi.pdfIn PDF document text
    • http://sportsclinicwest.ie/media/contents/file/26054508503.pdfIn PDF document text
    • http://remproekt-m.ru/admin/ckfinder/userfiles/files/71351391253.pdfIn PDF document text
    • http://gruaszarate.com/ckfinder/userfiles/files/59667566639.pdfIn PDF document text
    • http://www.clc-engineering.com/siteuploads/editorimg/file/5916261619.pdfIn PDF document text
    • https://unitytradefze.com/ckfinder/userfiles/files/kugenorerurogepogam.pdfIn PDF document text
    • http://yotlist.com/uniformkontakt/userfiles/image/files/munofatoturafu.pdfIn PDF document text
    • https://megashina24.ru/files/files/99808031538.pdfIn PDF document text
    • http://netichikawaya.com/userfiles/file/nekatejutebekovulagebu.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e71e937a73---71498374071.pdfIn PDF document text
    • http://gps-tw.com/CKEdit/upload/files/25454196022.pdfIn PDF document text
    • https://indicaperu.com/userfiles/file/39331196843.pdfIn PDF document text
    • https://alajuusa.ee/media/contents/file/53610482981.pdfIn PDF document text
    • http://wxmx.cn/upload/ckimg/files/202109072315173802.pdfIn PDF document text
    • http://bronnicy.inhome360.ru/admin/ckfinder/userfiles/files/94624835369.pdfIn PDF document text
    • http://aviatechinform.ru/sadm_files/rofopowak.pdfIn PDF document text
    • http://mxagproducts.com/upload/browse/file/2881394285.pdfIn PDF document text
    • http://crosswaysrecruitment.com/userfiles/file/97489991712.pdfIn PDF document text
    • https://genia-groupe.fr/images/files/90662599591.pdfIn PDF document text
    • https://www.adcgrain.com/wp-content/plugins/super-forms/uploads/php/files/e63b80d308b05fbcd1521190d3fc01e7/16978621493.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_off0000f25a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF25A 16944 bytes
SHA-256: 3cd7a7d52da8e54eacc640eb30f6d1b3d07ba7386fb7d7b492bec055af241375
font_01_sfnt_off00011e43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E43 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001365a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1365A 10580 bytes
SHA-256: 9d2db8bdf1853b827b67df917bff4af817135a7ae33f15c1b60786effc6debbd