Malicious PDF — malware analysis report

Static analysis result for SHA-256 7d54796291b3e0b2…

MALICIOUS

PDF

77.3 KB Created: 2021-09-19 14:46:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 1f30a0d139a18029fb8c61f9977e5185 SHA-1: c935b6b5f12b1d1929dd042bf8b0c34a8e4eb606 SHA-256: 7d54796291b3e0b291657137dd214aee60442f8f53a58c68f77c4d02a8bb6f0c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of numerous external links, many pointing to disposable hosting and utilizing UTM parameters, strongly suggests a phishing or malware distribution campaign. While no scripts were explicitly extracted, the PDF structure and link farm behavior are consistent with techniques used to redirect users to malicious sites.

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://medvor.ru/uplcv?utm_term=minecraft+gear+vr+edition+apk+download PDF link annotation
    • http://ricettebiagi.it/uploads/assets/file/7823839972.pdfIn PDF document text
    • http://maturitni-ples.eu/UserFiles/File/4452724064.pdfIn PDF document text
    • http://bhk-aindling.com/userfiles/files/48453914414.pdfIn PDF document text
    • http://dh-life.com/ckfinder/userfiles/files/jaxekegadokamanukutawupu.pdfIn PDF document text
    • http://studiodebiaggi.eu/userfiles/files/ximunakuxemafixesajopofom.pdfIn PDF document text
    • https://estduquebec.com/scripts/php/xenocode/lib/ckfinder/userfiles/files/zatutaxibuka.pdfIn PDF document text
    • http://www.frank-diagn.hu/userfiles/files/zeluravifotelanik.pdfIn PDF document text
    • https://sunnyvale.com/wysiwygfiles/file/wulozububalosoki.pdfIn PDF document text
    • http://760_709737661.mildmedia-dev.eu/uploads/userfiles/files/92031042030.pdfIn PDF document text
    • http://apartmany.cucoriedka.sk/data/files/pefubidutew.pdfIn PDF document text
    • http://teormech.ru/teormech/usrimg/file/99294838894.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136a41c68413---87436782113.pdfIn PDF document text
    • https://s-h.cc/uploads/files/202109170528123575.pdfIn PDF document text
    • http://doremimarlikinsaat.com/userfiles/file/fufemitutigapinani.pdfIn PDF document text
    • http://bijverhoeven.nl/uploads/files/xatekesowivuwaxefi.pdfIn PDF document text
    • https://gogift-it.com/userfiles/files/32891187191.pdfIn PDF document text
    • https://bepxuyenviet.com/upload/files/mizumarodili.pdfIn PDF document text
    • https://r4binsh4h9-att.com/contents/files/8392755154.pdfIn PDF document text
    • https://defi128.com/userfiles/files/23184642937.pdfIn PDF document text
    • http://lncxjzxxw.com/upload_fck/file/2021-9-14/20210914140157858375.pdfIn PDF document text
    • https://hashtag.school/userfiles/file/pevirikubuselikepow.pdfIn PDF document text
    • https://techson-cctv.com/upload/file/jidominevevujuzubagunab.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_off0000c755.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC755 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000df6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF6C 10864 bytes
SHA-256: bb80a076d7da2b8632376d8d34b48980ae192414ae8d1a88fb245e2f6347f4e8
font_02_sfnt_off0000f87e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF87E 18124 bytes
SHA-256: e919e79f1c9bd444244308c09e45e55864954a3e3dfc5c01a97ddf800bd6f7b1