Malicious PDF — malware analysis report

Static analysis result for SHA-256 81003d404033fb85…

MALICIOUS

PDF

69.6 KB Created: 2021-09-19 05:44:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 9f5628a505444be299c7e9feefe4746a SHA-1: 729495ef758bbb57d4611d096f320d9fa385b530 SHA-256: 81003d404033fb85cc99efe3f8e4a22f1680a48810ec6040535e292d1bde95c2
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is a PDF identified as malicious by ClamAV and an ML classifier. The 'SE_CALLBACK_LURE' heuristic indicates the document prompts the user to call a phone number, a common tactic in phishing and tech-support scams. While no scripts were directly extracted, the PDF structure and numerous embedded URLs suggest it's designed to redirect users to malicious sites or initiate fraudulent calls. The presence of many unknown URLs points to a link farm used for obfuscation or hosting further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 6

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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://grandviewgroupresort.com/upload/files/26494723937.pdf In PDF document text
    • https://chongtham68.com/app/webroot/uploads/files/lajakikoz.pdfIn PDF document text
    • http://entrackintl.com/uploads/5241115503.pdfIn PDF document text
    • https://discovercefalu.com/_data/images/file/naketepilogi.pdfIn PDF document text
    • http://jfhcoaching.nl/userfiles/files/wexuwujo.pdfIn PDF document text
    • http://www.c-l-r-p.com/admin/ckfinder/userfiles/files/mobadosivinoj.pdfIn PDF document text
    • http://decorstore.eu/upload/file/wikifot.pdfIn PDF document text
    • http://fishingas.com/userfiles/file/5273687875.pdfIn PDF document text
    • http://baovethanglongmb.com/upload/files/fogilal.pdfIn PDF document text
    • http://5mal4.de/moneyvidya/web/images/userfiles/file/guwajo.pdfIn PDF document text
    • https://volgogradexpo.ru/ckfinder/userfiles/files/14054398549.pdfIn PDF document text
    • https://duragloss.pl/userfiles/file/66761387557.pdfIn PDF document text
    • https://sofanet.ro/ckfinder/userfiles/files/4814116796.pdfIn PDF document text
    • https://tagoproperties.com/ckfinder/userfiles/files/59833922736.pdfIn PDF document text
    • https://thebookonpersonaltransformation.com/FCKeditor/file/83200187475.pdfIn PDF document text
    • http://etpatatietpatata.com/userfiles/files/30097886471.pdfIn PDF document text
    • http://haiphongcontest.com/images/files/41176849743.pdfIn PDF document text
    • http://kartywspomnien.pl/uploads/assets/file/lafupowezekumolasesalane.pdfIn PDF document text
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/161306898c801c---gitafazogedojejune.pdfIn PDF document text
    • http://horvathortho.hu/tmp/55691057645.pdfIn PDF document text
    • http://dui-antidote.net/images/userfiles/file/8984663277.pdfIn PDF document text
    • https://windfreeklima.com/upload/ckfinder/files/33392499172.pdfIn PDF document text
    • http://lamay.de/userfiles/file/dipani.pdfIn PDF document text
    • http://www.gyndoktors.de/ckfinder/userfiles/files/74701040492.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=how+to+stop+chrome+notifications+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_off0000b0ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0EF 15248 bytes
SHA-256: f1dba77b584e8cc9cd0b32575877cc0448854fabc65feaa44b384bb11834cf0e
font_01_sfnt_off0000d764.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD764 10916 bytes
SHA-256: 8ad285cf937d2e093a4191074708aae3162b24b613fca7137ad086a50c37887a
font_02_sfnt_off0000f08a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF08A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1