Malicious PDF — malware analysis report

Static analysis result for SHA-256 c99f5c1b923c3495…

MALICIOUS

PDF

68.8 KB Created: 2021-10-14 01:12:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 4c8b5302f25ecff0e88b6bfdb1f919b1 SHA-1: b37e0e0b19a29ec792f8515428121d6500087275 SHA-256: c99f5c1b923c3495b77398bbc33d3fa2aacf888072860b6f5e91e6aacfdda7ca
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics, including a machine learning classifier and ClamAV, indicating malicious intent. The PDF contains numerous embedded URLs, many pointing to potentially disposable domains, and is identified as a link farm. This suggests the document's primary purpose is to redirect users to external, potentially malicious websites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/92d152e243c287f922ea87e1e6abdf23/22033922702.pdf In PDF document text
    • http://studiocinti.eu/userfiles/files/27026689803.pdfIn PDF document text
    • http://symbioticlifetech.org/attfile/fckimg/file///20210906122438_736211633.pdfIn PDF document text
    • https://myreply.mobi/snappshott/editor//file/zufofesetimegatotukarar.pdfIn PDF document text
    • https://dom-titan.rs/files/mawuv.pdfIn PDF document text
    • http://fszhenjia.com/upfolder/e/files/20210918080126.pdfIn PDF document text
    • http://harekatmemuru.com/images/Media/files/80928496982.pdfIn PDF document text
    • http://www.hussco-steel.com/husscofiles/files/54466961580.pdfIn PDF document text
    • http://www.homefacelifters.com/wp-content/plugins/super-forms/uploads/php/files/e828a85044a5ec646cca3231b7e4e6a0/porik.pdfIn PDF document text
    • http://www.hangmandigital.com/files/file/buzasemuxi.pdfIn PDF document text
    • http://superfishinglewood.com/uploads/files/xosiril.pdfIn PDF document text
    • http://xn--90aoj0agf7cq.xn--p1ai/uploads/files/kerukimabef.pdfIn PDF document text
    • https://tlkingatlan.hu/kepek/other/file/43539018058.pdfIn PDF document text
    • http://rs-entp.com/upload/file/41686461024.pdfIn PDF document text
    • http://cancercareresearch.com/userfiles/file/9691663822.pdfIn PDF document text
    • https://burkina-businessschool.com/business_school/uploads/file/marevasezi.pdfIn PDF document text
    • http://studio-rivetti.it/userfiles/files/8475659565.pdfIn PDF document text
    • http://mascotdd.com/file_media/file_image/file/51337257114.pdfIn PDF document text
    • http://savemaxint.com/files/file/nalasegabilexenedomada.pdfIn PDF document text
    • http://coral-travel66.ru/admin/ckfinder/userfiles/files/zekawexugebi.pdfIn PDF document text
    • http://drapa-technika.cz/UserFiles/File/40332830016.pdfIn PDF document text
    • http://jongauger.com/ckfinder/userfiles/files/netidamemibetadomori.pdfIn PDF document text
    • https://onderhoudnlgarantie.nl/upload/file/34158928343.pdfIn PDF document text
    • http://heldermusic.nl/ckfinder/userfiles/files/dusopifin.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Gsjc/~3/KGDyd8lM0uI/uplcv?utm_term=marginal+distribution+two+way+tablePDF 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_off0000b130.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB130 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c947.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC947 10856 bytes
SHA-256: 10140c5ef3ba49e3b0b7e849afce9c45e81f2f2aa1064d491db7f0d2d26924a9
font_02_sfnt_off0000e257.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE257 14504 bytes
SHA-256: d41448f1c816360cf756aa251d5228e433444415b55295c10292a128d44ce33b