Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc4bc4609321d451…

MALICIOUS

PDF

80.6 KB Created: 2021-09-09 03:37:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d72eac2da47475f28d330293cc3af411 SHA-1: 16cdfe46056dcbaf329d15d58f8970500ec9a3f5 SHA-256: dc4bc4609321d4517130495e6670f56d5e180c295494f251da0f8c935926564c
164 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories, indicating a link farm designed to redirect users to potentially malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 7

  • 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.
  • 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 http://sanmorales.es/userfiles/files/47298674804.pdf
    • http://airsoft1.ro/files/file/jedopokilorekipawuwax.pdf
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/276f2a7674237e2fd9b2dcb73ffc3f07/89670725206.pdf
    • https://braviengenharia.com.br/wp-content/plugins/super-forms/uploads/php/files/b8ah69pjo100nve3nc36nuhl1i/feliwutemibilamufe.pdf
    • http://pro-group.ru/userfiles/file/fijewejelovavisupudavowom.pdf
    • http://borik.customreal.sk/data/files/jajaxurogelubijojodu.pdf
    • http://escrima-rlp.de/userfiles/file/52797754183.pdf
    • http://novastal.pl/userfiles/file/59957259735.pdf
    • https://zenithservicos.com/userfiles/files/92842586364.pdf
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613170e297432---xavexefijox.pdf
    • http://debten.net/UserFiles/File/kafik.pdf
    • http://powerfalcon.net/uppic/files/rigewabata.pdf
    • http://thebeautyofdesign.nl/ckfinder/userfiles/files/92873824113.pdf
    • http://sladkiy-ostrov.ru/userfiles/files/34697103210.pdf
    • https://www.vpn-solutions.com.pe/ckfinder/userfiles/files/dejugererelebusisine.pdf
    • http://www.39koratmachinery.com/file_upload/files/47173046628.pdf
    • http://beverleyannes.net/home/beverley/public_html/ckfinder/userfiles/files/36809982399.pdf
    • http://geyikkimya.com/userfiles/upload/file/30472326425.pdf
    • http://shahgrp.com/uploads/nimowumalazef.pdf
    • http://www.gleason.com.au/application/third_party/ckfinder/userfiles/files/58008450142.pdf
    • http://geomanteia.com/userfiles/files/nefuriku.pdf
    • http://tahyuh.com/uploads/files/202109061521158489.pdf
    • https://sankaibearing.com/userfiles/files/surififofa.pdf
    • http://csc021.com/userfiles/file/20210907174952_6kv060.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=intro+maker+premium+apk+download
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d450.bin
df0e08a8ab0c270f1bd487a9cc3d94fba00e6c9b026e85aec36d702b870671cf
pdf-font-stream PDF embedded font (sfnt) at offset 0xD450 18508 bytes
font_01_sfnt_off00010497.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10497 16792 bytes
font_02_sfnt_off00011cae.bin
b7a386be90274ad12c4e29b80c3be8b9b7e1d9f6aeea692d6a37b394eaa01b3f
pdf-font-stream PDF embedded font (sfnt) at offset 0x11CAE 10612 bytes