Malicious PDF — malware analysis report

Static analysis result for SHA-256 f990d28b657e88d0…

MALICIOUS

PDF

73.5 KB Created: 2021-09-12 19:47:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 3cf86ab490d360d0f60777ee03acf425 SHA-1: 3772a007de80643002e5deec03b5214629c08d0a SHA-256: f990d28b657e88d0b9afaa882de55c366a63fc12399c124f72a0ec55ea8e23ac
126 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, indicating a high likelihood of malicious intent. The presence of numerous embedded URLs, many pointing to disposable domains and configured as a link farm, suggests a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://energywork.pl/userfiles/file/bubawogojiroma.pdf In PDF document text
    • https://clic-essc.ch/ck/ckfinder/userfiles/files/gowubizuripewatexe.pdfIn PDF document text
    • http://sayarbobinaj.com/file/ribavodune.pdfIn PDF document text
    • https://senesi-sklad.cz/userfiles/file/29740255671.pdfIn PDF document text
    • http://tootingtaxi.com/survey/userfiles/files/53603526917.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613827bc4809e---fixasewo.pdfIn PDF document text
    • http://missteenqueenuk.com/userfiles/file/74343984377.pdfIn PDF document text
    • http://www.galiantsolutions.com/emailimages/file/70469441202.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/161338aec58a08---fugiromod.pdfIn PDF document text
    • http://xn--80aadcnaeutgftohcogh8i8dsc.xn--p1ai/pict/file/90279345022.pdfIn PDF document text
    • http://miass.realxenon.ru/uploads/files/75488390298.pdfIn PDF document text
    • http://misosmile.com/upload/editor/files/pogikujuteluzepasaj.pdfIn PDF document text
    • http://kadh.kr/bobod/upload/file/77526498065.pdfIn PDF document text
    • https://rireenfrance.com/images/upload/files/56647247185.pdfIn PDF document text
    • http://problemconsulting.com/img/download/files/tewelimovi.pdfIn PDF document text
    • http://mail-ex.net/userfiles/file/34714595060.pdfIn PDF document text
    • http://rocincorporated.com/domain.com/images/dynamic_pages/file/xagoluxepix.pdfIn PDF document text
    • http://jtg-antracyt.pl/files/file/redarawuzalazive.pdfIn PDF document text
    • http://tiramisu-o.com/yamituki-n/uploads/files/murojenige.pdfIn PDF document text
    • https://ikomsolutions.com/admin/userfiles/file/5316654115.pdfIn PDF document text
    • http://artpolyclinic.com/file/files/20501735926.pdfIn PDF document text
    • https://wisestudentz.com/userfiles/file/67919137487.pdfIn PDF document text
    • http://vinaktv.com/storage/ckfinder/files/fuduvowevetoze.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=how+to+get+data+from+old+phonePDF 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_off0000bd11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBD11 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d523.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD523 16688 bytes
SHA-256: 81c837bf5096dc991f042540a1022aaed4241574d755900ef43decc7211f9789
font_02_sfnt_off0000ffc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFFC7 10760 bytes
SHA-256: 85950f77a3e4ab3e83183bb233c8bde02f5c8d96ca0978f5c7e7d8d125adcfc6