Malicious PDF — malware analysis report

Static analysis result for SHA-256 d31c40b3c9519db7…

MALICIOUS

PDF

83.2 KB Created: 2021-09-19 20:11:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 592f3fcf5455b06f697b699ecbb0b811 SHA-1: f6183c4062ff1fa905aa3ecbb0cc3808fb8cf467 SHA-256: d31c40b3c9519db7692287c1dc374220b9a26e4e6f676f9fc6d2b6701835dddb
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document flagged by ML classifiers and ClamAV as malicious. Heuristics indicate it contains external URIs and a link farm, and specifically a callback phishing lure, suggesting it aims to trick users into contacting a fraudulent support line. While no scripts were extracted, the PDF structure itself is indicative of a phishing attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://www.lovebliss.tw/UserFiles/files/79106805941.pdf In PDF document text
    • http://kes.org/upload/editor/files/53749566133.pdfIn PDF document text
    • http://radioevangilereal.com/assets/ckfinder/core/connector/php/uploads/files/16491291722.pdfIn PDF document text
    • http://indexone.ru/upload/file/vemafaxupizetaduvoxapigu.pdfIn PDF document text
    • https://k-newsletter.com/ckupload/files/351965317.pdfIn PDF document text
    • https://ud-hobby.com/images/Upload/file/84266160473.pdfIn PDF document text
    • https://eliteswimmingpoolsinc.com/wp-content/plugins/super-forms/uploads/php/files/3vm0h9ugs0bbuhdhb77nb282l6/wupinokimusugumizepud.pdfIn PDF document text
    • http://gocep.org/data/userfiles/files/55416743657.pdfIn PDF document text
    • https://amzentransportationindustries.com/admin/imagetemp1/file/35411677241.pdfIn PDF document text
    • http://jianianhuayule.a9188.com/upload_files/art_files/files/20210903_053342.pdfIn PDF document text
    • http://hangquangauto.com/files/58842913158.pdfIn PDF document text
    • http://teusz.pl/UserFiles/file/13197081886.pdfIn PDF document text
    • http://www.jokilaaksonratsastajat.fi/file/91045657172.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/161390a01015a9---pemewokitozuro.pdfIn PDF document text
    • http://esenkardeslerinsaat.com/resimlerfiles/57528990945.pdfIn PDF document text
    • http://sooclose.eu/upload/File/71206548319.pdfIn PDF document text
    • http://shopcloud.cloud/ckfinder/userfiles/files/pigosuzofawogunedo.pdfIn PDF document text
    • http://driscollandgibson.com/images/edit_images/file/22009298436.pdfIn PDF document text
    • https://tidaksusah.com/contents/files/rifikuzone.pdfIn PDF document text
    • http://chothuethietbi.info/img/files/38389292992.pdfIn PDF document text
    • https://ww150007.linebot.net/upfile/files/20210917204942.pdfIn PDF document text
    • https://samsungvrvklima.com/upload/ckfinder/files/67553853051.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=gta+5+download+for+android+free+full+version+2020PDF 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_off0000e16e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE16E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f985.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF985 11016 bytes
SHA-256: 1e564e97bb1bd785624437c58c5a586322b69a924bc303b95f69f20e38bbdfbd
font_02_sfnt_off0001136e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1136E 16820 bytes
SHA-256: 8563c831841eae6edb3fcddc92966faf314d9ddcaf8c94d3230c027b4101976d