Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb4cb355ae3e2679…

MALICIOUS

PDF

83.4 KB Created: 2021-09-12 11:14:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 8382771e0908304a253ce1e88b45868c SHA-1: 5491b684f489c9ca2c92bdb19a6a1bb9104faca6 SHA-256: cb4cb355ae3e2679e6e8d48e224b7cd600238162ffafa752590508e74fee7b8c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many of which point to suspicious domains and are likely used to redirect users to phishing or malware hosting sites. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports its role as a link farm for malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://crystalnymph.by/wp-content/plugins/super-forms/uploads/php/files/454e868844471c9c65ed53fda1440ef3/jenusunapukasaketawopus.pdf In PDF document text
    • https://rakowka.pl/userfiles/file/fisebugaxenivekifajexewe.pdfIn PDF document text
    • https://www.bakkersvlaanderen.be/resources/plugins/ckfinder/userfiles/0/files/legan.pdfIn PDF document text
    • http://kuehllawpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/18095908399.pdfIn PDF document text
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/87eeb8bf7d2dd6dcf5d9bc1bb5e25466/wodofurabipesudesedapi.pdfIn PDF document text
    • http://wwsm-hk.com/files/file/matom.pdfIn PDF document text
    • http://unionasset.net/file_upload/spaw_upload/file/20210901223354.pdfIn PDF document text
    • http://shopcloud.cloud/ckfinder/userfiles/files/58756558169.pdfIn PDF document text
    • http://debeleven.net/UserFiles/File/delumeg.pdfIn PDF document text
    • https://ntc-container.com/upload/files/32349812391.pdfIn PDF document text
    • http://www.fd.ntou.edu.tw/ckfinder/userfiles/files/11401948412.pdfIn PDF document text
    • http://radyoislam.com/resimler/files/77798096418.pdfIn PDF document text
    • http://gradn.ru/uploades/fckeditorfile/84162362427.pdfIn PDF document text
    • http://classicalgardenornaments.com/uplds/file/20938406567.pdfIn PDF document text
    • https://bruceleevideos.org/images/file/60977513800.pdfIn PDF document text
    • http://kaiyudachem.com/filespath/files/20210910060115.pdfIn PDF document text
    • https://fullhousetourism.com/UploadFiles/file/20210909200230177.pdfIn PDF document text
    • https://siahotel.com/userfiles/files/gokemabuf.pdfIn PDF document text
    • http://artio.pl/files/files/xolabadesefixepibanija.pdfIn PDF document text
    • http://aid-calais.com/userfiles/file/93532098810.pdfIn PDF document text
    • http://ever0036.com/assets/uploads/ckedit/files/20210908103656.pdfIn PDF document text
    • http://cnzhongkui.com/fckeditor/editor/filemanager/connectors/php/uploads/file/050236213973.pdfIn PDF document text
    • https://anhhuynoithat.com/asset/files/jakowafi.pdfIn PDF document text
    • http://neoclassicalmansions.com/uplds/file/gifupenobanub.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=malaria+caloocan+zip+codePDF 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_off0000e221.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE221 17836 bytes
SHA-256: 73fed99c24d7bdf8465b84565d6a21a5fdaf4954bce773b2d793f3d1f22594b4
font_01_sfnt_off000110b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110B8 10296 bytes
SHA-256: 8f679f58ee672c61c357acaed8d00aeb9a3d89586dc235491fbc9c122b6272e6
font_02_sfnt_off000127fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1