Malicious PDF — malware analysis report

Static analysis result for SHA-256 4152a41214dd9039…

MALICIOUS

PDF

79.0 KB Created: 2021-09-10 17:49:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 604c5a1fe58f1b732328e0d9d5c3444a SHA-1: 8196806963781116b7e3f3db800188419582c834 SHA-256: 4152a41214dd90391cfc4721b35fa9a45dc08543189a167c371a685aa29a1db5
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to PDF files hosted on potentially disposable domains, indicating a link farm designed to redirect users to malicious content. The presence of a 'download' button heuristic further supports the lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

Heuristics 6

  • 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.
  • 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://flixgolf.com/ckeditor/ckfinder/userfiles/files/18883833638.pdf In PDF document text
    • http://bright-mineral.com/uploadfile/file/2021090823335995.pdfIn PDF document text
    • http://www.tractortools.cz/ckfinder/userfiles/files/55990814858.pdfIn PDF document text
    • http://www.amanuttarakhand.org/ckfinder/userfiles/files/goponeridu.pdfIn PDF document text
    • https://projetounificado.com/uploads/files/vulakinugujawemegemikinu.pdfIn PDF document text
    • https://zhansq.cn/upload/file/60903148212.pdfIn PDF document text
    • http://ayurveda-shiatsu-qigong-nice.com/upload/files/5748498781.pdfIn PDF document text
    • http://trans-serwis.com/userfiles/file/rigisepewefow.pdfIn PDF document text
    • http://hjhchem.com/upload/files/92038860292.pdfIn PDF document text
    • https://nationalshield-uae.com/userfiles/files/xixozaku.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/3lqgiddhr239pitia5teieuef4/rabuxovebimajek.pdfIn PDF document text
    • http://goksirlambinowice.pl/img/upload/files/75224417598.pdfIn PDF document text
    • https://abofahed.com/userfiles/file/vijonuruwetozapidisufiva.pdfIn PDF document text
    • https://mb-classic-service.de/userfiles/file/novibisopukalojafo.pdfIn PDF document text
    • http://munsusa.org/userfiles/file/20210902140507.pdfIn PDF document text
    • http://519pf.com/userfiles/files/saxuregufonizekeluwaw.pdfIn PDF document text
    • http://cinstech-inspect-survey.com/fckeditor_userfiles/file/puwavikini.pdfIn PDF document text
    • http://satit.nrru.ac.th/satit/_Adminis/ckfinder/userfiles/files/pinaronuruxese.pdfIn PDF document text
    • https://braindevelopmentmaps.org/userfiles/files/28956832054.pdfIn PDF document text
    • https://niagarablock.com/application/webroot/userfiles/file/newupomovilulewasor.pdfIn PDF document text
    • http://alkanboya.com/files/file///rawaliremo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=cemu+for+androidPDF 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_off0000d301.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD301 17144 bytes
SHA-256: cb8f3579a2cff107558d5854d2c0f13e910f787a6db4848e058640144c0ec85d
font_01_sfnt_off0000ff7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF7B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011792.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11792 10332 bytes
SHA-256: 95a5691b13c30358c07774bb356a27be1525fc6f95ce461009183d61e274e3c1