Malicious PDF — malware analysis report

Static analysis result for SHA-256 38c8b91e0214a834…

MALICIOUS

PDF

74.6 KB Created: 2021-09-18 19:01:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 736216e1ca54631b13d04b574a2afba4 SHA-1: 587ad9a8b4c46bfd799bf776eb1ebd7ebd429258 SHA-256: 38c8b91e0214a834b5f4a32643fe9039885f52a86a5d69573a1bc0165a1a7ee8
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to numerous external PDF files hosted on various domains. The presence of embedded URLs and the nature of the heuristics suggest an attempt to distribute malicious content or manipulate search engine results.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://medvor.ru/uplcv?utm_term=download+farm+city PDF link annotation
    • http://odesignlab.ru/admin/ckfinder/userfiles/files/diwazog.pdfIn PDF document text
    • https://soudurelauziere.ca/upload/editor/file/79456087359.pdfIn PDF document text
    • http://www.roosprommenschenckelfoundation.nl/ckfinder/files/files/xoratofusoxogafaj.pdfIn PDF document text
    • http://karmakonnect.org/DrumiBhatt/karmakonnect.org/Final/ckeditorimage/files/sifetokafoxaxukewaforub.pdfIn PDF document text
    • http://pmke.cz/pictures/files/36906452690.pdfIn PDF document text
    • http://king-tableware.com/uploads/files/202109041748455789.pdfIn PDF document text
    • http://dobraukraina.org/sites/all/sites/dobraukraina.org/files/giwikavo.pdfIn PDF document text
    • http://sarljarry.fr/userfiles/file/sofatesimefepujikobe.pdfIn PDF document text
    • https://coastalholidayproperty.com/ckfinder/userfiles/files/vemiwidinoru.pdfIn PDF document text
    • http://poney-club-romilly-aigre28.fr/userfiles/file/dogoge.pdfIn PDF document text
    • https://kaptenhoki.net/contents/files/zeguvogusanumokurupira.pdfIn PDF document text
    • http://dostrojar.sk/UserFiles/file/88612806160.pdfIn PDF document text
    • http://fandimnarodaku.cz/upload/file/67472527332.pdfIn PDF document text
    • https://podimercrm.com/img/files/nopenuxaxitedisiliraw.pdfIn PDF document text
    • http://srcchaika.ru/files/uploads/files/roxazozobepematedep.pdfIn PDF document text
    • http://xn----8sbfhu6ab4bqv.xn--p1ai/userfiles/file/19486880173.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/16131b0e3dbcbc---72611436528.pdfIn PDF document text
    • http://influences-vegetales.eu/assets/Image/files/23282268456.pdfIn PDF document text
    • https://vnjhanoi.com/upload/files/73643894023.pdfIn PDF document text
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/2ddf1745b2e64ccf413eae0a6255a679/gixukuvexuzema.pdfIn PDF document text
    • https://jazykovytabor.topenglish.sk/app/webroot/gallery/files/41081360577.pdfIn PDF document text
    • http://vallovin.it/userfiles/files/mevogudobemuzunemagidika.pdfIn PDF document text
    • https://hram-uspeniya.ru/ckfinder/userfiles/files/69181204261.pdfIn PDF document text
    • http://aybar-gallery.com/userfiles/files/99851805694.pdfIn PDF document text
    • http://geologicatoscana.eu/userfiles/files/lurijiruvet.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/68148697481.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_off0000c582.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC582 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dd94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD94 15556 bytes
SHA-256: acb556ffabca7c805d96562225d9ffc4fa43d7d41edf54b28203a49023da49cb
font_02_sfnt_off000104de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104DE 10540 bytes
SHA-256: 701c542df0c11bbb3b526a8d44cf70671ec0c950c4120460f68b9f3f19b8e04e