Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8d8833ce524c8b9…

MALICIOUS

PDF

72.9 KB Created: 2021-09-20 07:52:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: b97387ba72b07d92238d3d82ec952143 SHA-1: a3f1711e83f3376eb51e79a2bcaf9300f94f93c4 SHA-256: b8d8833ce524c8b97fe8749168c920d84976d127e1c17da5077bd79f6c89a59a
156 Risk Score

Malware Insights

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

This PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised WordPress upload directories or disposable hosting, indicating a link farm designed to redirect users. The presence of these links suggests an attempt to lure users to external sites, likely for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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 https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/kjnhun2gngr7tucqberqrpird2/bafatizudiwaza.pdf In PDF document text
    • https://thaiahpa.com/flash/files/35618564391.pdfIn PDF document text
    • http://flex-link.cn/uploadfiles/files/6110044671.pdfIn PDF document text
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613909b340074---51914647554.pdfIn PDF document text
    • http://tythb.com/uploadfile/files/fasulalowikamelisapole.pdfIn PDF document text
    • http://hsound.ro/images/custom/file/duvukinejoxufi.pdfIn PDF document text
    • http://oshcongregation.com/userfiles/file/63907967377.pdfIn PDF document text
    • http://dgjst.com/upfile/file/81319128610.pdfIn PDF document text
    • http://scoutpate.com/userfiles/file/nakobipufuwupa.pdfIn PDF document text
    • http://aqcorth.specialty-match.com/upload/files/75107222561.pdfIn PDF document text
    • https://duocvinhkim.com/userfiles/file/kudamuw.pdfIn PDF document text
    • https://jotekonybakterium.hu/userfiles/files/podawunorewigevetanixa.pdfIn PDF document text
    • http://moderncarrent.com/user_img/files/godokeromozigudoteturomir.pdfIn PDF document text
    • http://videocycling.info/files/file/92646658544.pdfIn PDF document text
    • https://przygodanaukrainie.pl/admin/ckfinder/userfiles/files/kevizipo.pdfIn PDF document text
    • https://provisionsinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140c08519334---95821209140.pdfIn PDF document text
    • https://broadcasthub.com/ci/userfiles/files/32615292381.pdfIn PDF document text
    • https://hkbca.org/UploadFiles/file/20210912071026109.pdfIn PDF document text
    • http://nilesk.com/userfiles/file/37483739127.pdfIn PDF document text
    • http://iuoooo.com/filespath/files/20210913182204.pdfIn PDF document text
    • https://saintarseny.ca/sites/saintarseny.ca/files/file/96531944993.pdfIn PDF document text
    • http://rmgoals.com/userfiles/files/12685491643.pdfIn PDF document text
    • http://altadirezione-consulting.it/userfiles/files/77485297106.pdfIn PDF document text
    • http://p-itos.net/admin/userfile/image/file/60941450705.pdfIn PDF document text
    • http://kpnauto.com/UserFiles/file/85474614690.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=price+of+redmi+note+10s+in+nepalPDF 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_off0000b98e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB98E 10956 bytes
SHA-256: 6ce016823cc7c9afc30946ec68d00386d7758d13970ed066a959ee7248548dd6
font_01_sfnt_off0000d2f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD2F9 16556 bytes
SHA-256: 5e1be8dce802e9127f6ab6fe9bc6c73aefb0085cb9eef9e2f4e6ba4d919f156f
font_02_sfnt_off0000fd97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD97 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1