Malicious PDF — malware analysis report

Static analysis result for SHA-256 811262b32058cac5…

MALICIOUS

PDF

81.4 KB Created: 2021-09-21 02:48:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 2c84463a7bdb90e985b6a153294e8a29 SHA-1: f6ca104f9ce6fbe47f8500e3a1ccc7b9b039944c SHA-256: 811262b32058cac561f8fe9646622d5a2c1905836a4c1691e6f71f325543ac54
126 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm. The numerous embedded URLs, many pointing to disposable domains, suggest an attempt to obscure the final destination, likely a phishing page or a download site for further payloads. No scripts were extracted, but the structure and URL patterns are consistent with phishing lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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 https://wtmasonry.com/ckfinder/userfiles/files/98326514222.pdf In PDF document text
    • http://ivelinabozilova.com/userfiles/file/7034331511.pdfIn PDF document text
    • https://zohopin.com/calisma2/files/uploads/73302692181.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/161427fd7d221b---48174801776.pdfIn PDF document text
    • https://pro-biomed.com/admin/userfiles/file/55858461988.pdfIn PDF document text
    • http://de-ko-gmbh.com/ckfinder/userfiles/files/3985061543.pdfIn PDF document text
    • http://global-leasing-management.com/uf/file/24202532529.pdfIn PDF document text
    • http://sziazsauto.com/uploads/files/febaguxi.pdfIn PDF document text
    • https://newsale.linyn.mobi/upload/ckeditor/pages/files/kopufeleberuwu.pdfIn PDF document text
    • https://topclassgreenery.nl/images/file/13954958561.pdfIn PDF document text
    • https://www.leasing.net.in/ckfinder/userfiles/files/65069133934.pdfIn PDF document text
    • http://irs-messtechnik.at/upload/7434606713.pdfIn PDF document text
    • http://officegate.biz/admin/fck_upload/file/natugixu.pdfIn PDF document text
    • http://mingmitrcoffee.com/user_img/files/mevigeduxipag.pdfIn PDF document text
    • https://clubesolbra.com/uploads/files/90405447102.pdfIn PDF document text
    • http://mzch.pl/userfiles/file/68230735553.pdfIn PDF document text
    • http://kwik-it.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161408cc16184e---21797665837.pdfIn PDF document text
    • https://vyrukrc.lt/userfiles/file/82017562914.pdfIn PDF document text
    • https://ladachess.ru/userfiles/file/29201127286.pdfIn PDF document text
    • http://snft.ro/media/file/pageledibanin.pdfIn PDF document text
    • http://bouwbedrijfansing.nl/userfiles/file/36791912870.pdfIn PDF document text
    • http://tjsyjdq.com/v15/Upload/file/202192036593818.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=misbehaving+thaler+pdfPDF 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_off0000d8cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8CB 10856 bytes
SHA-256: 432cd7644d26412874d849bce916d309594e4db34ee0bd9d8839b737c6fd7d86
font_01_sfnt_off0000f16c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF16C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001097e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1097E 18208 bytes
SHA-256: 235b1ad562cc04898ac45dfe758f8f8fa7117a644d71690f198fab4e7222c6d5