Malicious PDF — malware analysis report

Static analysis result for SHA-256 52cdfab55f0d3027…

MALICIOUS

PDF

95.8 KB Created: 2021-07-19 00:33:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: a5dff16e46786f7b71f8e139448a78db SHA-1: 8d4b4c8c124157ba95985b3c55ce3289358134b1 SHA-256: 52cdfab55f0d3027614ef1deef44a82cffe6c6185b6ce10ea7edf6d671410b44
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised CMS upload directories, specifically WordPress sites. These links are designed to appear as PDF files, likely to deceive users into downloading further malicious content or visiting phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d9348854953---59290185725.pdf In PDF document text
    • https://fajanav.com/aym_image/files/36291347904.pdfIn PDF document text
    • http://yaqeen-eg.com/userfiles/file/33492054841.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/c75e049971cd36a9e99b6a2ecbecfc1f/mojapika.pdfIn PDF document text
    • https://www.onestopnaturalstore.ca/wp-content/plugins/super-forms/uploads/php/files/ip1jknk9tj6vp9r6j54mvrpk6k/20876561786.pdfIn PDF document text
    • https://doellefjelde-mussemarked.dk/images/newsmail/file/90440944519.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa0bd0a7482---20033018823.pdfIn PDF document text
    • http://optykglowacki.pl/obrazki/files/74932937753.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16098e2181273b---87423748979.pdfIn PDF document text
    • https://outsourcedbackoffice.co.uk/wp-content/plugins/super-forms/uploads/php/files/a1463a1bcc67546b26c3bdf42333d360/85738084453.pdfIn PDF document text
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/c7g9m1o8cilhj1u6kc94e2vvv4/56207921971.pdfIn PDF document text
    • https://arizonapoolcontractor.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f3ebe79b4c---xiwefowepume.pdfIn PDF document text
    • http://garderoba.sk/images/_file/sodeboxadepujumijuru.pdfIn PDF document text
    • https://castel.ro/userfiles/file/dakalojixemotefikexoxag.pdfIn PDF document text
    • http://riverbendhay.com/clients/4/4e/4e1cbd84181290ddb66fb035c9950ff6/File/beritiludurawi.pdfIn PDF document text
    • https://www.marvistasales.com/wp-content/plugins/super-forms/uploads/php/files/0205fb98d19fb565bc4378f8508df6b9/79388450788.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/5524c4bef086b496ea55ecaabd5209b4/97229964799.pdfIn PDF document text
    • http://bona-agra.pl/Upload/file/rizazojoxov.pdfIn PDF document text
    • http://apexnepaltravel.com/userfiles/file/varanadedoduk.pdfIn PDF document text
    • https://mfdesign.hu/files/file/67648770473.pdfIn PDF document text
    • http://pobierzplik.pl/uploads/files/83239296522.pdfIn PDF document text
    • https://www.wflorlando.com/wp-content/plugins/super-forms/uploads/php/files/30741b07534cdf6b1ac7adb8475deaeb/jiwosetowunabon.pdfIn PDF document text
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/52975d6393daea19de89ceb87f251813/gejif.pdfIn PDF document text
    • https://aprilboya.com/userfiles/file/19424781358.pdfIn PDF document text
    • http://ledson.ru/upload_picture/82458491288.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=badly+bruised+thighPDF link annotation
    • 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_off0001161f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1161F 16740 bytes
SHA-256: 58f162d8d3b151958039ac63a80096160c90828387f935f0c1590b977e3ed7ae
font_01_sfnt_off000141be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x141BE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000159d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x159D5 10712 bytes
SHA-256: 77de0910a4df085d428d7be73b6544b4b13cfaa006431d9284596ec57b9c1568