Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c648cd10c22aa37…

MALICIOUS

PDF

112.1 KB Created: 2021-09-20 19:51:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 3fef39bfada676ceff14db98dd98b2e2 SHA-1: 4c542073592d83c95cebec85517fb3613e62ae23 SHA-256: 1c648cd10c22aa37cde25155e142e98829f6dfc38d4a9fd6c3a54adcac9aedab
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, specifically as a phishing trojan. It contains numerous embedded URLs, many pointing to disposable domains, characteristic of a link farm designed to distribute malicious content or phish for credentials. The `PDF_SEO_DISPOSABLE_LINK_FARM` heuristic further supports this, indicating a large number of links on potentially untrustworthy hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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 http://hyundaiokla.com/uploads/files/67476061195.pdf In PDF document text
    • http://triple-a.co.th/ckfinder/userfiles/files/39352092569.pdfIn PDF document text
    • https://www.tcf.gov.tr/ckfinder/userfiles/files/47580457863.pdfIn PDF document text
    • http://moscreen.in/cmsfiles/file/jutot.pdfIn PDF document text
    • http://amoy-art.com/Upload/file/57127835560.pdfIn PDF document text
    • http://turinhotelcompany.com/userfiles/files/mekapolabilali.pdfIn PDF document text
    • https://wickedcheesy.com/images/file/fuguvixoloba.pdfIn PDF document text
    • http://kubablimel.pl/Image/files/19424876859.pdfIn PDF document text
    • https://matricula.netlandschool.cl/files/faxupijunisuloje.pdfIn PDF document text
    • http://xn----gtbercbfedtm3b.xn--p1ai/admin/ckfinder/userfiles/files/xukuxesubu.pdfIn PDF document text
    • http://someteme.com/archivos/_20210905132153.pdfIn PDF document text
    • http://potlista.com/file/files/ruroxuxabuvewasowifu.pdfIn PDF document text
    • http://imobilestore.de/userfiles/file/gebodeb.pdfIn PDF document text
    • http://revistaspontan.ro/assets/ckfinder/core/connector/php/uploads/files/91430817284.pdfIn PDF document text
    • http://bctlorraine.org/userfiles/file/35336138845.pdfIn PDF document text
    • http://fruitsad.pl/images/file/nonotofozonomuwemopedod.pdfIn PDF document text
    • http://xn--90aoa5aj.xn--p1ai/ckfinder/userfiles/files/lodumike.pdfIn PDF document text
    • https://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/uekmehrnpnm01ah954gomahl0r/fatewinidese.pdfIn PDF document text
    • http://tctrack.vn/images/newtech/files/fefivid.pdfIn PDF document text
    • http://www.enredmail.com/templates/files/idCliente_/file/rufalejisidivudaretotus.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/161478ecc0d13a---49812263455.pdfIn PDF document text
    • http://okna-dvere-online.cz/media/upload/upload/file/50342255554.pdfIn PDF document text
    • http://asbu.net/uploads/FCK_files/file/lolodepa.pdfIn PDF document text
    • http://theclelandgroup.com/img/upload/file/48875014008.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=david+copperfield+text+pdfPDF link annotation
    • https://mediaget.com/userfiles/files/82162944342.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_off0001502a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1502A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00016841.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16841 10512 bytes
SHA-256: 008b82207d4e1f6ca2372eabb0b272489048b49fe1950fbde428794de0ff55b5
font_02_sfnt_off00018050.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18050 18740 bytes
SHA-256: f5f11752fa9f3bf5d0b9cd211c44ea1bb031d4209a99cfa37b71edaa4d070b08