Malicious PDF — malware analysis report

Static analysis result for SHA-256 921e700fa5624ee0…

MALICIOUS

PDF

75.5 KB Created: 2021-10-02 22:54:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 08efbae0b034374f166a5199d635d398 SHA-1: 9fea5d68314fbe977826fc2201aa33a5f8a93d45 SHA-256: 921e700fa5624ee08990ea7d74c5a7670ffb88a7fdf1c9ad5f4109e0f281593f
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to compromised WordPress sites, suggesting a lure to download a password-protected archive. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure and heuristics point to a social engineering attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613023c2dc469---zefaronakesimaba.pdf In PDF document text
    • https://shih-tzu.ro/files/file/61072586819.pdfIn PDF document text
    • https://rabudiagnostic.com/userfiles/files/54416335433.pdfIn PDF document text
    • http://autoscuolecasetta.it/userfiles/files/54380402930.pdfIn PDF document text
    • http://spartapr.com/images/upload/file/55816674470.pdfIn PDF document text
    • https://angkorphotographyguide.com/userfiles/file/6980761192.pdfIn PDF document text
    • https://telliogluhukuk.com/userfiles/file/laxoriwe.pdfIn PDF document text
    • https://liantoong.com/archive/upload/files/pidirepokotafijubunetora.pdfIn PDF document text
    • http://xn--oy2b19v1mb1yi.com/userfiles/file/lugadegegu.pdfIn PDF document text
    • http://serbanindustrialconstruct.ro/uploads/files/zifefuguwibawexazupixoten.pdfIn PDF document text
    • https://airxps.com/userfiles/files/84339307105.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614e699a155f5---muwifakalowebitujos.pdfIn PDF document text
    • http://theshop24.com/userfiles/file/libipukujekavewamumor.pdfIn PDF document text
    • http://tischtennis-kiel.de/images/file/27811565389.pdfIn PDF document text
    • http://brukbet.com/user_images/file/suzekedesuve.pdfIn PDF document text
    • http://matrix-corporation.com/upfiles/editor/files/kuwidulazofuxiru.pdfIn PDF document text
    • https://webhosting4.net/media/file/45048152852.pdfIn PDF document text
    • http://saatgaamkansarasamaj.com/admin/uploads/files/fereperexejase.pdfIn PDF document text
    • http://rinsacars.com/files/others/13907815965.pdfIn PDF document text
    • https://cissud.eu/uploads/ck_editor/files/nabufutetilokow.pdfIn PDF document text
    • https://efckrakow.pl/userfiles/file/49387906631.pdfIn PDF document text
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/161434e9c1ff00---soniragapalexasurur.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=how+do+i+get+my+pdfs+to+open+in+separate+windowsPDF 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_off0000b5ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB5EA 21024 bytes
SHA-256: 4b82ac226430ea9f983b5b18454c4ff915049d14ebe4fbcd8dea46af200c8f1f
font_01_sfnt_off0000ecd3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECD3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000104ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104EA 10988 bytes
SHA-256: 87b9a6a77369dbd30366579121eb67ca7f5b4f196d84fadfa1e16e3be162d633