Malicious PDF — malware analysis report

Static analysis result for SHA-256 da044499e109520a…

MALICIOUS

PDF

82.3 KB Created: 2021-09-10 03:22:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: b9033b8d0803ecd5612b533d7d465b81 SHA-1: fde821d4b694a0e815f40e01cfca1fd9cf37d85a SHA-256: da044499e109520aaa18804ad5a4ee654ba3c454831c6ee8319d4919b960e363
174 Risk Score

Malware Insights

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

The PDF contains multiple heuristic firings indicating malicious intent, including random and disposable URLs, and a critical ClamAV detection for a phishing trojan. The presence of numerous external links, some pointing to potentially malicious domains, suggests the document is designed to redirect users to download further malicious content. The ML classifier also strongly indicated maliciousness.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://partner-support.net/user_data/userfiles/files/ruvezutokinifu.pdf In PDF document text
    • https://jlgardner.org/home/jlg/public_html/ckfinder/userfiles/files/xovonufafizusanewatilaboz.pdfIn PDF document text
    • http://bmcnx.com/userfiles/file/rafumejirilibedimulax.pdfIn PDF document text
    • http://piotrkowska77.pl/zdjeciafile/10880722815.pdfIn PDF document text
    • http://qiangka.com/ckfinder/userfiles/files/vuwevotidutenemafebowedox.pdfIn PDF document text
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134098599d5f---27939872560.pdfIn PDF document text
    • https://pensionradvanice.cz/res/file/jesapegimafajolidutadun.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a90566c388---96900468466.pdfIn PDF document text
    • http://trips-in.com/ckupload/files/37861726632.pdfIn PDF document text
    • https://ev-owners.jp/userfiles/files/kifanuzobute.pdfIn PDF document text
    • https://burkina-businessschool.com/business_school/uploads/file/vuxekakadon.pdfIn PDF document text
    • http://phanphoiongnhuahoasen.vn/upload/files/44950516594.pdfIn PDF document text
    • http://dochoiotovn.com/uploads/userfiles/file/66421914195.pdfIn PDF document text
    • https://szaniterplaza.hu/ckfinder/userfiles/files/mitodesesikowevilegidare.pdfIn PDF document text
    • http://ambulatorioveterinariocigliano.com/userfiles/files/95645146544.pdfIn PDF document text
    • http://93564497.com/userfiles/vexegipi.pdfIn PDF document text
    • https://himalmanpower.com/ckfinder/userfiles/files/43420315269.pdfIn PDF document text
    • http://gespk.com/userfiles/file/wijevetaraniramufeziteg.pdfIn PDF document text
    • https://probidjp.com/ckfinder/userfiles/files/20210910_065327.pdfIn PDF document text
    • https://www.eos.org.eg/ckfinder/userfiles/files/75312095942.pdfIn PDF document text
    • http://falconartistmanagement.com/ckfinder/userfiles/files/gexisukijenodorasazuxiga.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=the+alchemy+of+finance+pdf+downloadPDF 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_off0000d9c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f1d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1D7 18896 bytes
SHA-256: 90c6b9a364ff77242f8996961e1793552c4de1ae9893da7471816b9f1511b8a4
font_02_sfnt_off00012336.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12336 10680 bytes
SHA-256: 23ec922edb1b3831993cacd2a130b9544db4fe6f465089dc0a4ec5d0fe0e04ca