Malicious PDF — malware analysis report

Static analysis result for SHA-256 9c9766ccc6f15a94…

MALICIOUS

PDF

78.3 KB Created: 2021-09-19 08:23:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e57364cee7b042221a4e8bbb6254c862 SHA-1: 8c9d1cd89b6918aaf220a15d09d87cf3d2874bca SHA-256: 9c9766ccc6f15a94d40063d63abc561dc053169bc15fe9ff7d34b9fdfe258b11
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link T1059.007 JavaScript

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting it functions as a link farm. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically indicates this behavior, likely to redirect users to phishing sites or download further malware. No scripts were extracted, but the PDF structure itself facilitates the malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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
  • 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://irlanc.ru/uplcv?utm_term=tachyon+vpn+download+apk
    • http://hk-sai.com/ckfinder/userfiles/files/97675363719.pdf
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/161329ac10b2cc---zaduzime.pdf
    • http://ser-buk.com/userfiles/file/pexutanavawiw.pdf
    • https://avukatwebsitesi.trakyasoft.com/upload/files/mimawagimuvisabisikafajal.pdf
    • https://kompaspt1.com/contents/files/zidakejub.pdf
    • http://arohitourandtravels.com/userfiles/file/77270399618.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/161402e2bcaf74---33914776832.pdf
    • https://lexcochoralsoc.org/demo/lccs/beta/userfiles/files/61436550975.pdf
    • https://bbpartner.cz/userfiles/file/fajed.pdf
    • http://travel-door.com/userfiles/file/68240425961.pdf
    • https://lekkermooi.nl/userfiles/file/zozimuxetujefegal.pdf
    • http://xn--66-6kc8bfmkmjd.xn--p1ai/admin/ckfinder/userfiles/files/duvopesuk.pdf
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140947312e5e---gilutuzunazex.pdf
    • http://vasekurzy.cz/userfiles/file/fowujefepuje.pdf
    • https://weborder.cloud/userfiles/file///44482409424.pdf
    • http://heryeryesil.com/resimlerfiles/pefomerapuvigepezitedegib.pdf
    • http://rfychina.com/upfiles/files/16319088052849.pdf
    • http://joinsocialbubble.com/cake/beta/userfiles/file/monifebej.pdf
    • http://qdsenfeng.com/data/files/48309356099.pdf
    • http://tiramisu-o.com/yamituki-n/uploads/files/32753109743.pdf
    • https://nenmongdangquang.com/upload/files/54408488631.pdf
    • https://livstyle.ro/home/livstyle/public_html/uploads/files/miwixarowojimodetuxoxab.pdf
    • https://biomedchita.ru/imeg_master/file/zufolor.pdf
    • https://radmangroup-ye.com/rgfiles/file/83442008448.pdf
    • https://questyme.ca/userfiles/file/28541670623.pdf
    • 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_off0000cbe0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCBE0 16792 bytes
font_01_sfnt_off0000e3f2.bin
f8956d2681bd4bf7dbbfcaf43c0f5ec55aa0153fd9ba817831aba144676fd236
pdf-font-stream PDF embedded font (sfnt) at offset 0xE3F2 18424 bytes
font_02_sfnt_off000114ab.bin
72d6954b462ca01ed9dffa207c568626af7c78ba5e4623d2a0042be45b8481f9
pdf-font-stream PDF embedded font (sfnt) at offset 0x114AB 10340 bytes