Malicious PDF — malware analysis report

Static analysis result for SHA-256 829df9190515bebc…

MALICIOUS

PDF

70.7 KB Created: 2021-09-01 01:12:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: b1b9ee244f8fa7d1a3409208e7de0b17 SHA-1: fa92abeee4a1b40e9d7571008fbf9cedd734efa7 SHA-256: 829df9190515bebce2cb801e11cf1ee7d2e9ca24c4be22044a08f80d03ad1566
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The file was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. Multiple heuristics indicate the PDF contains numerous links pointing to external PDF files hosted on various domains, many of which appear to be compromised CMS upload directories. The primary purpose seems to be distributing or linking to other malicious documents, potentially for SEO poisoning or further infection chains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://www.bordadoindustrial.com/ckfinder/userfiles/files/jagisewokanebakukizirekow.pdf In PDF document text
    • http://ankamet.com/userfiles/file/bibexonetek.pdfIn PDF document text
    • https://hophamthaibinh.com/upload/files/xadotibosodikutonevele.pdfIn PDF document text
    • https://www.vedaaz.com/wp-content/plugins/super-forms/uploads/php/files/05c56a14e4c8c8af0315e18265b64954/jodunapaxogelesiw.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/160ac161de6473---jajutazavifevozo.pdfIn PDF document text
    • http://alpha-th.com/userfiles/file/65184835093.pdfIn PDF document text
    • http://lovelyspa.net/ckfinder/userfiles/files/kibepodunoxaxite.pdfIn PDF document text
    • https://bosgo.mn/uploads/files/gajilifusexigupuzi.pdfIn PDF document text
    • http://easyliveconstruction.com/ci/userfiles/files/98231935832.pdfIn PDF document text
    • http://fipjp.com/userfiles/file/xofulik.pdfIn PDF document text
    • https://coloreverything.love/wp-content/plugins/super-forms/uploads/php/files/a22c4c0fcf41dce64bf150ade8e1fc52/71027953544.pdfIn PDF document text
    • http://jjc-dev.com/userfiles/file/pofirakeju.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/228b26a291aa70b4307144332c7faf8b/50019864024.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fcb7efef97d---lisatojo.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/36ee2bab151f211521296a85538159f0/rafixakasap.pdfIn PDF document text
    • http://pillshop.ru/uimg/files/15491753231.pdfIn PDF document text
    • https://www.hinogas.com/wp-content/plugins/super-forms/uploads/php/files/ip67jin7iromjab8jl968835g1/gujepezigeduvabol.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c1fd31171f---13846357330.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/6e2a9fc73e7e6c5e4ccf9c2182010173/29540403941.pdfIn PDF document text
    • http://paitoonbox.com/userfiles/files/walonolinesetimeme.pdfIn PDF document text
    • http://maslag.eu/userfiles/file/54377025483.pdfIn PDF document text
    • http://abwferrellpkwy.com/uploads/files/fefojizabubetekelezape.pdfIn PDF document text
    • https://asmitahrgroup.com/ckfinder/userfiles/files/vexewudo.pdfIn PDF document text
    • http://rittenhousereunion.com/clients/a/ad/ad7d26974070b67854a29702aed78614/File/80846661790.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=from+celsius+to+kelvinPDF 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_off0000b841.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB841 10464 bytes
SHA-256: 464bc60a08d1ce97d6a21a008885e5bb92406b29cb7caf7ba7a51314c10828a6
font_01_sfnt_off0000d001.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD001 14944 bytes
SHA-256: 97340d5898b7148f7d42a7366cded145a477d8050e7ffabe9ed287aa3ff8c8d3
font_02_sfnt_off0000f589.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF589 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1