Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b5c7e910efffbe0…

MALICIOUS

PDF

74.8 KB Created: 2021-09-12 13:03:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 9530fdb5607e6d5ec54c5796a12d5e99 SHA-1: 7d3816ca5ac1452220a1af3d1233e42d13faa645 SHA-256: 7b5c7e910efffbe04c765d4fd6f84ed0bff63df7f93970c9c28f7d8048c95b41
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable domains and are structured as a link farm, a common tactic for phishing or distributing further malware. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic confirms the nature of these links.

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 http://kosmonautika.ee/ckfinder/userfiles/files/51713164372.pdf In PDF document text
    • http://nicenpos.com/userData/board/file/xazesadatagesijamasuse.pdfIn PDF document text
    • http://averon.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16134a75c3e499---midisutozonus.pdfIn PDF document text
    • http://tccsrl.org/userfiles/files/36563167510.pdfIn PDF document text
    • http://nwatchonline.org/userfiles/file/84928994024.pdfIn PDF document text
    • https://deltarents.com/upload/ckfinder/files/tirogasabasovoneze.pdfIn PDF document text
    • http://uco-kampen.com/media/files/mukapesurefake.pdfIn PDF document text
    • http://chanhungcorp.com/images/uploads/files/vufezodususurixupatoxib.pdfIn PDF document text
    • http://mgbig.com/upload_fck/file/2021-9-9/20210909044421781664.pdfIn PDF document text
    • http://www.centrosanmarco.eu/img/news/files/kusawigagab.pdfIn PDF document text
    • https://nezrenweb.com/calisma2/files/uploads/relisagamogatorasen.pdfIn PDF document text
    • http://laarakkers.com/ckfinder/userfiles/files/pedalu.pdfIn PDF document text
    • http://ivankrivanek.com/userfiles/file/93702310573.pdfIn PDF document text
    • http://bowenlawmt.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/voxusodoposabotevege.pdfIn PDF document text
    • http://hosungtour.net/FileData/ckfinder/files/20210909_35A690724C347F39.pdfIn PDF document text
    • https://bisleriuber.genefied.co/ckfinder/userfiles/files/56972602956.pdfIn PDF document text
    • http://tourbusan.net/FileData/ckfinder/files/20210910_021F3C7E6BCFEB68.pdfIn PDF document text
    • https://malabarmail.com/ckfinder/userfiles/files/vonev.pdfIn PDF document text
    • http://9262895.ru/ckfinder/userfiles/files/wilexejujaxivosuponofup.pdfIn PDF document text
    • http://escalierdurire.fr/ckfinder/userfiles/files/sowusugaxubira.pdfIn PDF document text
    • https://aluvioneschicamocha.sinecsas.com/ckfinder/userfiles/files/soselefumu.pdfIn PDF document text
    • http://fandimnarodaku.cz/upload/file/saxepinojupuzezipapinape.pdfIn PDF document text
    • https://ljlconst.com/admin/images/file/fevewewoxoripuxabenake.pdfIn PDF document text
    • http://konberdbio.com/upload/files/dodideruteleseviv.pdfIn PDF document text
    • http://gapp.fr/medias/files/kapekota.pdfIn PDF document text
    • http://xn--2-140-swe8h.xn--p1ai/files/woxuboxomifunibim.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=apk+webview+sistem+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_off0000c5e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5E5 10872 bytes
SHA-256: 185f61af64edb20f403d2e256bd7c81ac1e0772d0db07731586a59b300f41b85
font_01_sfnt_off0000dee2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEE2 15272 bytes
SHA-256: 1350ab5aec5c446aabbe78da4ce61647c3d5067e59828270176827620425f142
font_02_sfnt_off00010528.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10528 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1