Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b55d3b285e172a9…

MALICIOUS

PDF

77.7 KB Created: 2021-10-10 15:17:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-03
MD5: 2168949b27fd8170fd48ba9f6d0f4dfb SHA-1: 708b93f541518fef00a613b961e04302902318e1 SHA-256: 1b55d3b285e172a99d902ea875a905c980feff04f47dd9b78f591b0b964ecc63
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM indicates the document is part of a link farm, and the presence of external URIs suggests an attempt to redirect users. While no scripts were explicitly extracted, the PDF structure and malicious verdict strongly suggest it's designed to lead users to malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://engineersclasses4competition.com/files/others/9458932607.pdf In PDF document text
    • http://fantasymusic.it/userfiles/files/vifetubujibeforu.pdfIn PDF document text
    • http://physio-praxismitte.de/userfiles/73902214532.pdfIn PDF document text
    • http://tw-tms.com/uploadpic/xw/files/xevusu.pdfIn PDF document text
    • http://songpinhao.com/userfiles/files/82802894816.pdfIn PDF document text
    • http://podarox.ru/public/files/46493931097.pdfIn PDF document text
    • https://totounited.com/contents/files/xexumusa.pdfIn PDF document text
    • http://coca-colalife.eu/userfiles/file/79405644645.pdfIn PDF document text
    • https://eastmangroup.org/ckfinder/userfiles/files/zitawanukafukoluwuzeboj.pdfIn PDF document text
    • https://virtrade.gr/userfiles_lybo/file/35771951250.pdfIn PDF document text
    • http://travellightnepal.com/userfiles/file/22757279075.pdfIn PDF document text
    • http://www.hgbehringer.de/img/files/files/58642711121.pdfIn PDF document text
    • http://zechnerbau.at/images/content/files/65223244452.pdfIn PDF document text
    • http://somkuthyoptika.hu/editor_up/xolevo.pdfIn PDF document text
    • http://asfalon.com/__files/file/xawusalanomul.pdfIn PDF document text
    • https://egyptsuntours.com/userfiles/files/3485876306.pdfIn PDF document text
    • http://americasbestwingsbeltsville.com/uploads/files/vifodonesazizowejag.pdfIn PDF document text
    • https://www.hinkler.com.au/application/third_party/ckfinder/userfiles/files/megazagunivinimapogar.pdfIn PDF document text
    • https://hobbypet.cz/files/file/79519742711.pdfIn PDF document text
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/b09eacb8bc664c5c209ae45031009518/49062274407.pdfIn PDF document text
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/2c82cb782c9c1d9ccbb50e851a19f0a0/9768123288.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=negative+connotation+of+homePDF 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_off0000ca63.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA63 10512 bytes
SHA-256: 0675e4c230eba975d2130e8f59f8234582b85804ba9838e330d9577bd2b5a457
font_01_sfnt_off0000e22d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE22D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fa3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA3F 18144 bytes
SHA-256: b32020f5f9f6107c88e0e462d5991bc64e595a621946dd2d9c67be1a6aff6371