Malicious PDF — malware analysis report

Static analysis result for SHA-256 ea2b63ec1c7ccce8…

MALICIOUS

PDF

80.0 KB Created: 2021-09-14 02:54:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 589c0a0a4a5ee66c78d105298c71284f SHA-1: 759ecd7ca8dab5e39dfde61611d2211a853bc751 SHA-256: ea2b63ec1c7ccce83974df052cec5a6086552a6cfde3f4a20865a5973af91d78
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous links to external PDFs hosted on various domains, indicating it functions as a link farm. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically flags this behavior, suggesting a phishing or malware distribution scheme. No scripts were extracted, but the presence of multiple external links points towards an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://elskup.pl/images/assets/file/pudemaxo.pdf In PDF document text
    • http://www.zaluziemalina.cz/userfiles/file/xawogibok.pdfIn PDF document text
    • http://captaincook.hu/userfiles/file/28553295364.pdfIn PDF document text
    • https://investir-petroleo.pt/ckfinder/userfiles/files/wozalugokovox.pdfIn PDF document text
    • https://www.helpfulhunks.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16136f812d1823---6158709599.pdfIn PDF document text
    • http://daglichtfilters.nl/ckfinder/userfiles/files/vorisaxalifanosufaluxuna.pdfIn PDF document text
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/5b8821cbe2d41887ab1e2ee920bd010e/fixado.pdfIn PDF document text
    • http://ohana1bbq.com/uploads/files/9314760076.pdfIn PDF document text
    • https://awinresource.com/uploadfile/file/vegekodumi.pdfIn PDF document text
    • https://burkina-businessschool.com/business_school/uploads/file/35851988377.pdfIn PDF document text
    • http://xycrusher.com/d/files/suwolabere.pdfIn PDF document text
    • http://mq-water.net/upload/duguxisabolaxewufozodij.pdfIn PDF document text
    • http://keystoparadise.com/userfiles/files/tozitemonodanasurokawibov.pdfIn PDF document text
    • https://inprovitecuador.com/ckfinder/userfiles/files/40948363906.pdfIn PDF document text
    • https://music-group-store.com/upload/files/49420044743.pdfIn PDF document text
    • http://hong-tour.com/FileData/ckfinder/files/20210901_E781C46EF65F6B04.pdfIn PDF document text
    • http://agcslohian.com/userfiles/file/1485698153.pdfIn PDF document text
    • http://abcbyspu.net/ckfinder/images_store/files/jumosikilizebevumojed.pdfIn PDF document text
    • http://sintjorisparochie.nl/userfiles/file/bigera.pdfIn PDF document text
    • https://hilanguage-com-tw.triangle-design.com/files/89215897326.pdfIn PDF document text
    • https://asiapharma.la/files/files/10053991723.pdfIn PDF document text
    • http://softtox.pl/new/userfiles/file/fufoxusilinokitiluzeva.pdfIn PDF document text
    • https://asoriofrio.org/ckfinder/userfiles/files/93649957109.pdfIn PDF document text
    • http://makeyourpartnermelt.com/userfiles/file/xenobuduwatenazo.pdfIn PDF document text
    • https://maximatrimony.com/ckfinder/userfiles/files/35929780383.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=past+modals+of+deduction+exercises+pdf+with+answersPDF link annotation
    • https://lapdonline.org/file/11240682538.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_off0000cff2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFF2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e809.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE809 11172 bytes
SHA-256: ac5316af58cbd28a200939f326d8b50abe195dd71069a16073a0d5eba857969e
font_02_sfnt_off00010204.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10204 18396 bytes
SHA-256: 30d829f645e79a980b73a66c092d2b07b0285544b5b0f750699e6530f70b1f9b