Malicious PDF — malware analysis report

Static analysis result for SHA-256 1e4b31dfe0ec9bdb…

MALICIOUS

PDF

81.6 KB Created: 2021-09-18 01:57:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 49375a2062a1f5c7791e8d24f2a3e45f SHA-1: ebd86cb7a395dc51ce7bfbe6d2a3a983e78fd7c8 SHA-256: 1e4b31dfe0ec9bdb241b6df1ff3b28d906bf87dc4fb7393ac2d1cdd2976d11e6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, with multiple heuristics indicating it functions as a link farm. The embedded URLs, such as 'https://crysiq.ru/uplcv?utm_term=nomedia+file+android', likely lead to phishing or malware download sites. Although no scripts were explicitly extracted, the PDF format can embed JavaScript, which is often used in such attacks to redirect users or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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
  • 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://crysiq.ru/uplcv?utm_term=nomedia+file+android PDF link annotation
    • http://www.ebsjosepirosamaria.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cb2b708cd2---1404613339.pdfIn PDF document text
    • http://dongduong.net/Images_upload/files/40422650995.pdfIn PDF document text
    • https://vnsteeldetailing.com/UserFiles/files/kixadabaradobulivefidebo.pdfIn PDF document text
    • https://luxm.pl/userfiles/file/momufoperedupapofuv.pdfIn PDF document text
    • https://tennis-samara.ru/img/file/50077707517.pdfIn PDF document text
    • https://jbdclothiers.net/emailer/userfiles/file/jamililurupinanolefi.pdfIn PDF document text
    • https://ce-mi.pl/uploads/userfiles/files/86323031497.pdfIn PDF document text
    • http://tetobox-budapest.hu/uploads/files/kisaxuvixox.pdfIn PDF document text
    • http://portaldeaquidauana.com.br/ckfinder/userfiles/files/55405954983.pdfIn PDF document text
    • https://cortemadera.com/wysiwygfiles/file/6024049371.pdfIn PDF document text
    • http://glassick.com/userfiles/file/faxakife.pdfIn PDF document text
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/834b4d9b12216bc5c6df0a469cb790c4/95527944755.pdfIn PDF document text
    • http://duonglaohanoi.com/userfiles/file/10255844964.pdfIn PDF document text
    • https://lesura.net/userfiles/file/83232099339.pdfIn PDF document text
    • http://www.ciesol.es/ckfinder/userfiles/files/2014977627.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612edb85d65f3---pubanobamezujuvorugataza.pdfIn PDF document text
    • http://teormech.ru/teormech/usrimg/file/5900870268.pdfIn PDF document text
    • http://angelcabrera.com/FCKfiles/file/dosunan.pdfIn PDF document text
    • http://mt-filtration.com/uploaded/file/1936237896136b75688696.pdfIn PDF document text
    • http://gonvvama.net/filespath/files/20210902120636.pdfIn PDF document text
    • http://techsystem.gr/data/uploads/ckeditor/files/ruxuratijifopoxudase.pdfIn PDF document text
    • http://rockycheng.com/ckfinder/userfiles/files/fojebuxirabotez.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f71689656d---vuwilenedatasapalawodafel.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_off0000dcf7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCF7 17500 bytes
SHA-256: df2456c1f780a51400eb654cf16b912405724e5aba6195baa75006d1b66accaf
font_01_sfnt_off00010a08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A08 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001221f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1221F 10224 bytes
SHA-256: 9d50b4d31b46e4e0145c7f01cb4ded7aed1cfb297a1030b1cc6103295fe0c06b