Malicious PDF — malware analysis report

Static analysis result for SHA-256 f21e42ae7e73fcc3…

MALICIOUS

PDF

71.6 KB Created: 2021-09-26 07:05:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 3b2d366332aed4a19df30c7ca0101def SHA-1: 12ac5664038f6f8a0acc88d9e59e73896be1ce5c SHA-256: f21e42ae7e73fcc3d521d5716dac2fe48957e0bbf474b9a3872816f9957558c1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URLs, many of which are hosted on disposable domains and appear to be part of a link farm, a common tactic for phishing or distributing further malware. The PDF structure and embedded URLs suggest it's designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://garglob.ru/uplcv?utm_term=letters+that+starts+with+k PDF link annotation
    • http://3gr-group-com.gbintl.com/ci/userfiles/files/63670767014.pdfIn PDF document text
    • http://teakdeck.pl/files/file/69813798865.pdfIn PDF document text
    • https://www.sudoku-cool.com/ckfinder/userfiles/files/68672695039.pdfIn PDF document text
    • https://premium-house.uz/images/file/dalaxojorodinadubepi.pdfIn PDF document text
    • http://grandfiltr.com/files/file/rilodarumapanozawifopej.pdfIn PDF document text
    • http://signauction.net/userfiles/file/57941540618.pdfIn PDF document text
    • https://habibitoursegypt.com/ckfinder/userfiles/files/61935402147.pdfIn PDF document text
    • https://sk-elektron.ru/ckfinder/userfiles/files/natarurowiros.pdfIn PDF document text
    • http://oroblupiscine.it/userfiles/files/xeninu.pdfIn PDF document text
    • https://anmoul.com/userfiles/file/laligitimojikoluke.pdfIn PDF document text
    • http://bephoangdung.vn/uploads/ckfinder/files/maval.pdfIn PDF document text
    • http://koreaticketland.com/userfile/file/3814988165.pdfIn PDF document text
    • http://globalbando.com/DATA/upload/files/202109120306188226.pdfIn PDF document text
    • http://kelvista.lt/images/files/8143674470.pdfIn PDF document text
    • https://ekselantechnology.solutions/ckfinder/userfiles/files/wipavonubevujekujawotus.pdfIn PDF document text
    • http://boardmark.com/files/file/4224901787.pdfIn PDF document text
    • http://marcobernini.it/userfiles/files/xorolofunonaxal.pdfIn PDF document text
    • https://coonvalleycc.com/userfiles/file/zejonenep.pdfIn PDF document text
    • http://naturpix.ch/cmsimages/file/xopefifodemi.pdfIn PDF document text
    • https://tfsroanoke.com/home/tfs/public_html/new/ckfinder/userfiles/files/35799067175.pdfIn PDF document text
    • http://fence-alarm.com/userfiles/files/87200217852.pdfIn PDF document text
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/ca4fa67eb02dfd81907a6477da384153/81457142403.pdfIn PDF document text
    • http://agapetown.net/ckfinder/userfiles/files/74805392157.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_off0000b468.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB468 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cc7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC7F 10072 bytes
SHA-256: 1c7129a7ba98a0f39dd91e3d6de475cbd162e409c587c332b617d8569b51cad4
font_02_sfnt_off0000e322.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE322 18064 bytes
SHA-256: 8922f319ce451cf611900df794f4dd1836366b87abbaeed56160097fc72de51d