Malicious PDF — malware analysis report

Static analysis result for SHA-256 55f1184d504bcee4…

MALICIOUS

PDF

81.2 KB Created: 2021-10-10 01:11:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 64b15dbaaf7c5cbaa8d72799c6d2324b SHA-1: 469609fc418144dde5830863f9514103f7cb8a07 SHA-256: 55f1184d504bcee4d780aae57258ab9f5dacc3588021212fd36bfecd755dd72b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URLs, with one heuristic specifically identifying it as a link farm on disposable hosting, suggesting a phishing or redirection scheme. Although no scripts were explicitly extracted, the PDF structure and heuristic firings point towards an attack pattern involving the exploitation of PDF vulnerabilities or social engineering to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://thuduchouse.vn/pics/file/mimawax.pdf In PDF document text
    • http://masterkontroll.hu/ckfinder/userfiles/files/18604979623.pdfIn PDF document text
    • http://maytinhnangdong.com/files/uploads/editor/files/92618380637.pdfIn PDF document text
    • http://secretinvitation.net/images/files/rogewujuroxaj.pdfIn PDF document text
    • http://unixsensor.com/uploads/files/202109011017411375.pdfIn PDF document text
    • https://wintechindia.in/ckfinder/userfiles/files/31126567299.pdfIn PDF document text
    • http://urjabatteries.in/userfiles/file/bemazezoxam.pdfIn PDF document text
    • https://mudraconsultancy.com/uploads/files/77824236277.pdfIn PDF document text
    • https://anjingliar2.com/contents/files/difikewexuferibilun.pdfIn PDF document text
    • https://lexcochoralsoc.org/demo/lccs/beta/userfiles/files/jipimefozumoxeja.pdfIn PDF document text
    • https://leganordavigliana.com/uploads/file/38849919630.pdfIn PDF document text
    • https://sanagustin.cl/files/93612080847.pdfIn PDF document text
    • http://sujitonweb.com/userfiles/files/80419695559.pdfIn PDF document text
    • https://torgradio.ru/new/files/file/50377978165.pdfIn PDF document text
    • https://deltarealestate-eg.com/userfiles/file/79145423553.pdfIn PDF document text
    • http://symbolfoods.com/files/file///74269411542.pdfIn PDF document text
    • http://asupuro.com/upload/save_image/files/zulegakasapobugotiti.pdfIn PDF document text
    • http://vakoplus.cz/klienti/devel/sneznerolby.cz/ckfinder/userfiles/files/dugitev.pdfIn PDF document text
    • https://www.serwkom.pl/plugins/ckfinder/userfiles/files/xeriletawaboregatope.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/31542357276.pdfIn PDF document text
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/4f53921db1f540c2a3e3817e1d84be2d/1458728458.pdfIn PDF document text
    • https://inprovitcentroamerica.com/ckfinder/userfiles/files/zeviv.pdfIn PDF document text
    • https://mimpiindah168.com/contents/files/74055632537.pdfIn PDF document text
    • https://greenfuturevietnam.com/Upload/files/logumujarukeru.pdfIn PDF document text
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/80d44f70fddd19a638fd1c4355ae9d48/lagujumomovil.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=instruction+manual+for+ps3PDF 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_off0000d3c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3C6 10732 bytes
SHA-256: ef4170d4fe5b986c6d470ddd10e14cc13230fe9f53cc874f7606b5f8c4625692
font_01_sfnt_off0000ec6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC6C 19484 bytes
SHA-256: 19e7aea2226e10fa8c63d93de44ce8434e4f0dfb5feb19a205394f3f8c68bbb2
font_02_sfnt_off00011f61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F61 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1