Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b30b3726acbc6eb…

MALICIOUS

PDF

85.9 KB Created: 2021-09-24 10:14:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 9ceb4cc5728a4136670919c735f4c7a8 SHA-1: 826eb353ebac4a2c2022d3b3c6a0f72638c2c1bd SHA-256: 5b30b3726acbc6eb251d56e8fa6304c42c7da0cb23a58f81ab58a2e335a35270
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by a machine learning classifier and ClamAV. It contains numerous embedded URLs, many of which are part of link farms hosted on potentially disposable domains or compromised CMS upload directories. The primary attack pattern observed is the use of these links to direct users to external, potentially malicious, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://easytravel63.ru/ckfinder/userfiles/files/94455590165.pdf In PDF document text
    • https://tramtron.vn/uploads/files/files/49668855975.pdfIn PDF document text
    • http://pro-group.ru/userfiles/files/87279904478.pdfIn PDF document text
    • http://btsoft.vn/uploads/files/wiwonatasimak.pdfIn PDF document text
    • https://simon-daulte.com/ckfinder/userfiles/files/40830994895.pdfIn PDF document text
    • http://bellina.pl/userfiles/file/65556457559.pdfIn PDF document text
    • http://ytlcases.com/userfiles/file/25513799528.pdfIn PDF document text
    • http://myxroad.net/upload/userfiles/file///tosorogojofimo.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/161442ac92dbdd---89807553217.pdfIn PDF document text
    • http://www.letnifestiwal.pl/ckfinder/userfiles/files/vonejet.pdfIn PDF document text
    • http://dep14kirov.ru/userfiles/file/68194017590.pdfIn PDF document text
    • http://www.anglometais.com.br/adm/Editor/ckfinder/userfiles/files/36266802307.pdfIn PDF document text
    • http://rsentco.com/upload/file/40123535474.pdfIn PDF document text
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/8jeorpoac7rhb1lv2h1aj583j4/27600930657.pdfIn PDF document text
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/5039e054f6d6c2b1d5021d9d7f9785da/butapirupup.pdfIn PDF document text
    • https://yomadesign.com/userfiles/Proj_Name/files/zatavaxefud.pdfIn PDF document text
    • http://bluebiz.kr/userData/board/file/jikubaji.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614d2d24b6ed1---bidul.pdfIn PDF document text
    • http://diamant-x.sk/UserFiles/file/50839934708.pdfIn PDF document text
    • http://aokisuper.com/ckfinder/userfiles/files/78505764704.pdfIn PDF document text
    • http://phamtrangia.site/upload/files/43945534522.pdfIn PDF document text
    • http://hockjoohin.com/admin/uploads/file/kavinewo.pdfIn PDF document text
    • https://drbumbnursinghome.in/ckfinder/userfiles/files/34905554220.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=city+of+ashes+read+onlinePDF 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_off0000ea15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA15 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010227.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10227 18444 bytes
SHA-256: 0c263124d92f0be22828ee1c7028fb516eb7c4616084743581ac9f8043d2e41e
font_02_sfnt_off00013224.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13224 10596 bytes
SHA-256: de61284bf749d0e6c09e42b46dc075b4c8f0ebe934ad4a613d280dac59c8471d