Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b4bf731f7897ce4…

MALICIOUS

PDF

91.4 KB Created: 2021-09-09 03:55:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: c12aa6ae5268085706dd511851a8117e SHA-1: 9eb7362bdb3f4f511d25d2c6c6e564177c30fa38 SHA-256: 6b4bf731f7897ce48de3e4e269e45e9a9ea63e124c8498311e14249adb9ac145
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which are part of a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware via the embedded links. The presence of JavaScript suggests an attempt to execute code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://archism.ru/uplcv?utm_term=2007+playboy+kim+kardashian PDF link annotation
    • http://peneleos.pl/userfiles/file/93364665326.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613483953a260---19631185349.pdfIn PDF document text
    • https://tch.lu/files/files/nusofekusowixovesoxisog.pdfIn PDF document text
    • http://tbff-bygg.se/img/files/zasegejekowajapolugikiko.pdfIn PDF document text
    • https://thehideawayresortpattaya.com/userfiles/files/xelasemuvixirobut.pdfIn PDF document text
    • http://murito.fr/ckfinder/userfiles/files/zexesezerigu.pdfIn PDF document text
    • https://otoform.com/upload/ckfinder/files/jujaluralepisetoxopajob.pdfIn PDF document text
    • https://producedepot.us/userfiles/files/16017067400.pdfIn PDF document text
    • http://zensushialiso.com/uploads/files/96084317071.pdfIn PDF document text
    • http://www.nachtruhe.info/up/files/kisegijitapupafonaxizaj.pdfIn PDF document text
    • http://chhattisgarhsanskritboard.in/sharpinstitute/images/files/13238038030.pdfIn PDF document text
    • http://gachtrangtritranvinhtin.com/gachtrangtritranvinhtin/Images_upload/files/rovapenizudunuzuvexe.pdfIn PDF document text
    • http://altus.pl/userfiles/file/34292465145.pdfIn PDF document text
    • https://aluvioneschicamocha.sinecsas.com/ckfinder/userfiles/files/kajusozesokotuto.pdfIn PDF document text
    • http://ptaki.info/imgekoprojekty/files/fuzunirumasitokebida.pdfIn PDF document text
    • https://cutletsmeat.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133b4af2531a---fasigotutelobe.pdfIn PDF document text
    • http://s-privod.ru/userfiles/file/43471392255.pdfIn PDF document text
    • http://zhymwz.com/upfile/file/bixigiminaleso.pdfIn PDF document text
    • http://asea-admin.com/_userfiles/file/20210909081546.pdfIn PDF document text
    • https://silatur.com/js/ckfinder/userfiles/files/fakijikapuziza.pdfIn PDF document text
    • http://nwatchonline.org/userfiles/file/96035244590.pdfIn PDF document text
    • http://ride.hu/images/uploads/files/wediputomifo.pdfIn PDF document text
    • http://koreaseowon.com/ckupload/files/xiluxudozogu.pdfIn PDF document text
    • https://allcondosales.rodeodrivecondosale.com/userfiles/files/zadojavakipatujogazupa.pdfIn PDF document text
    • http://karate-talence.com/newsite/userfiles/files/22136550449.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_off0000fe61.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE61 10968 bytes
SHA-256: 5c52e37c6698eb6ed16085bf71a1357df19f87c244af7159a6bd25a390285593
font_01_sfnt_off0001176f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1176F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012f81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F81 18732 bytes
SHA-256: 88876f8052caa03634fdd00d86f444d0c82cabe23dd650b8c38a8128457ed0dd