Malicious PDF — malware analysis report

Static analysis result for SHA-256 3e826cbb667bdea1…

MALICIOUS

PDF

84.2 KB Created: 2021-09-04 20:38:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 606bb6faf3bfaa1695cac6b9acfcec4b SHA-1: fdeedc50ce349695c76ca2a5c16f239efe06cb32 SHA-256: 3e826cbb667bdea1ee099884d61f6c9dde2596892d4f03469a04e5bf918be496
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs that point to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of these URLs and the heuristic firings indicate an attempt to deliver a secondary payload or phish for credentials.

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://smidgel.ru/uplcv?utm_term=organiza+tu+closet+mental+pdf PDF link annotation
    • http://dansensvenner.dk/imagesfile///47032783292.pdfIn PDF document text
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c0f2954b35a---wuzovo.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/16071eb88c7ac6---49240782152.pdfIn PDF document text
    • https://otdelkamos.ru/wp-content/plugins/super-forms/uploads/php/files/6b2cc21cb172cabcfa7679ebd0ef43c3/26235870241.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/k5t1j127bh0rqecof2pdt8uv06/46318947536.pdfIn PDF document text
    • https://www.entornopublicitario.com/wp-content/plugins/super-forms/uploads/php/files/ca81b679054ddf9fdf235595a05501e1/48388403066.pdfIn PDF document text
    • http://maduraigarlandshop.com/userfiles/file/wikixosaluw.pdfIn PDF document text
    • http://machinegroup.ru/img/outer/files/zokokanenitizekemopopekek.pdfIn PDF document text
    • http://kco.su/userfiles/file/xonaliginazasutepevaka.pdfIn PDF document text
    • http://sun-green.de/ckfinder/userfiles/files/76560047461.pdfIn PDF document text
    • http://chapraptti.org/userfiles/file/fanabenuporixopez.pdfIn PDF document text
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/18klaag6k1f25uhbm7fndofkns/39888088540.pdfIn PDF document text
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d04f9d29b3---17608589627.pdfIn PDF document text
    • https://efnnma.org/files/file/86074598341.pdfIn PDF document text
    • http://jenan.com/ckfinder/userfiles/files/32517940712.pdfIn PDF document text
    • http://macap.nl/app/webroot/files/userfiles/files/15837791797.pdfIn PDF document text
    • https://ptogel2.com/contents//files/minojizalitid.pdfIn PDF document text
    • https://argumentua.com/i/file/62189824450.pdfIn PDF document text
    • http://b-solutions.net/userfiles/file/nozulukurad.pdfIn PDF document text
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/ikfrd5b2aj31401j0cr6v27096/puguridijopaneveno.pdfIn PDF document text
    • http://nationshield.ae/userfiles/files/23668854218.pdfIn PDF document text
    • 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_off0000e111.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE111 11148 bytes
SHA-256: 2cf2452386f39fd2393b95e81f19e93ba685b3f1073d8ff3fe470913baef33f8
font_01_sfnt_off0000fafa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAFA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001130c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1130C 18420 bytes
SHA-256: 11abe9d03aa25c25aed04431a0a87ecb57973db2d96c72e0c1c65706235df266