Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c858b462d1eb87a…

MALICIOUS

PDF

77.3 KB Created: 2021-09-15 13:06:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 27b57f101f87c1f40d6ae75bcf28cc35 SHA-1: c50076c109846e9422b2de1af5407f1b9a0770d6 SHA-256: 4c858b462d1eb87a1bdac15df827e35db367bb54f403a2d4987435ddc5ef32f5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as a malicious PDF by ML classifiers and ClamAV. It contains numerous external links, many pointing to compromised websites or disposable hosting, suggesting a link farm designed to redirect users. The presence of 'utm_term=bet365+app+android+free+download' in one URL indicates a potential phishing lure for a betting application. While no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://philabc.ru/uplcv?utm_term=bet365+app+android+free+download PDF link annotation
    • http://zpb-maciejewski.pl/upload/fck/file/35576617400.pdfIn PDF document text
    • https://amatnieks.lv/pictures/image/89396054160.pdfIn PDF document text
    • http://noithatnhapkhaugiasi.com/luutru/files/47112412592.pdfIn PDF document text
    • http://servicedental.it/userfiles/files/pogejikigijimomoxa.pdfIn PDF document text
    • http://eng.sut.ac.th/tce/2016/administrator/ckfinder/userfiles/files/pewiletezev.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613552bcdc841---17231749128.pdfIn PDF document text
    • https://fminterativa.net/cms/plugins/ckfinder/userfiles/files/mozebezusagijogudo.pdfIn PDF document text
    • http://gccde.com/downloads/blog/geust/files/lituvamel.pdfIn PDF document text
    • http://ohmytour.kr/FileData/ckfinder/files/20210905_5ED3C77B990AFB6F.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/oshu1h6gtae9sutk1id2pggjf5/vozamumov.pdfIn PDF document text
    • http://pieseclimaauto.com/files/file/dosuvejanitawuwewikuruf.pdfIn PDF document text
    • http://ahjygjg.com/upload_fck/file/2021-9-11/20210911075416647953.pdfIn PDF document text
    • http://audidalys.lt/ckfinder/userfiles/files/bupijikowapuv.pdfIn PDF document text
    • https://francois-daulte.com/ckfinder/userfiles/files/22253926118.pdfIn PDF document text
    • http://cabinet-blin.fr/ressource/site-image/files/binibadexuxipemuwi.pdfIn PDF document text
    • https://turkeyinsurance.info/images/file/renamesasezavege.pdfIn PDF document text
    • http://busankid.com/webfiles/board/file///88633162824.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/5rl8678h4i4lrb9fld6a3n2von/46961156983.pdfIn PDF document text
    • http://thuephotocopytaihanoi.com/upload/files/tuledoraxuvusebaxazuxas.pdfIn PDF document text
    • http://thibangoto.com/app/webroot/uploads/files/tixisoginijoverawex.pdfIn PDF document text
    • http://marinda.ru/pics/images/file/71725032830.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_off0000c80a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC80A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e021.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE021 10936 bytes
SHA-256: 0908c7dad9864b1c41e588b8b17846a020d79aa7d36037d9f0cfd42fc724c048
font_02_sfnt_off0000f9a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9A9 18000 bytes
SHA-256: 9a87eefd6b76b1ac16640b3b3cd77bceb29bafd483df591e2c69701dd2eedbd8