Malicious PDF — malware analysis report

Static analysis result for SHA-256 1231ba874a81143f…

MALICIOUS

PDF

90.7 KB Created: 2021-09-20 03:59:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 318310137a6e7f50916e432ae2aa38b7 SHA-1: f3e3e11f5de07aaf45383335f5a65d48d5e6aa71 SHA-256: 1231ba874a81143f54fcd35ec2d52b1f9c10aa1a241f1cf12b6e8c8585085e2e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristic analysis revealed it functions as a link farm, embedding a large number of URLs, many of which point to potentially malicious or unknown domains. The document's structure and embedded links suggest an attempt to direct users to external resources for malicious purposes, likely phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://parfumerieindex.nl/images/uploads/22051957216.pdf In PDF document text
    • https://edinburghpools.com/contents/files/96206228412.pdfIn PDF document text
    • http://mediaworld.pro/ckfinder/userfiles/files/repalisiboso.pdfIn PDF document text
    • https://galerie-louise.be/userfiles/files/jimozonogixomu.pdfIn PDF document text
    • https://aannemingsbedrijfbarthulsbosch.nl/userfiles/file/lusemofowarefi.pdfIn PDF document text
    • http://zmz72.ru/files/file/28882605440.pdfIn PDF document text
    • http://letdentalab.com/img/files/16394391378.pdfIn PDF document text
    • http://pharmabiosolutions.com/filespath/files/20210909165503.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/161361ba078cdc---63426915444.pdfIn PDF document text
    • http://thailaundry.com/imgUpload/files/8588370946.pdfIn PDF document text
    • https://kstraders.com/userfiles/file/76642094625.pdfIn PDF document text
    • https://brawlcall.jordanadams.com/ckfinder/userfiles/files/62429094992.pdfIn PDF document text
    • http://wgadget.com/file_media/file_image/file/didamizivitilutopadi.pdfIn PDF document text
    • https://kocarbon.vn/luutru/files/98835433804.pdfIn PDF document text
    • https://vanphongphamhienluong.com/upload/files/72288271545.pdfIn PDF document text
    • https://childprotectionindia.com/lexcyberia/userfiles/files/mogexoxoxuxudibijasasuril.pdfIn PDF document text
    • http://pinzimoniofiumicino.eu/userfiles/files/povusamaki.pdfIn PDF document text
    • https://learn-atdi.com/uploads/files/basidinubiwunune.pdfIn PDF document text
    • http://topnotchimports.com/ckfinder/userfiles/files/23115727517.pdfIn PDF document text
    • https://christianbelieversmatrimony.com/web/christiansbelieversmatrimony/photos/ckeditor/files/56438187551.pdfIn PDF document text
    • http://bestbelly.org/content/files/files/nuvuxejizi.pdfIn PDF document text
    • http://gwardiajuvenia.pl/zdjecia/fck/file/lejofojivatetadoful.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=hello+guest+apk+androidPDF 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_off0000f8d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000110e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110E8 19408 bytes
SHA-256: 0e69d0452b2d9a71c807cbd89212d7f592c0786c73b15ea9778bdf74b9b45140
font_02_sfnt_off000144b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x144B3 10748 bytes
SHA-256: 6be3060649214e6d509c6a917d4d021034636a1f1db2afe2058bd7342fcd1ac1