Malicious PDF — malware analysis report

Static analysis result for SHA-256 27f9099e6085bbbc…

MALICIOUS

PDF

68.4 KB Created: 2021-10-03 17:37:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 7d1f48b9c6501ea6480e200b544359e6 SHA-1: 039c96664a4161dbcea270e905aeebc7f0cea1a8 SHA-256: 27f9099e6085bbbc9add81dd99921bfd84b0fb8be9b099b3728dfe71cd460ced
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to compromised CMS uploads and disposable hosting. These links likely lead to further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/4j7mbe3b05a9h6k5hrlvsl34mh/37108995561.pdf In PDF document text
    • https://gpuhub.net/wp-content/plugins/super-forms/uploads/php/files/ge5n3v1uf2sk4pui0qlisodpni/batemudodimusorala.pdfIn PDF document text
    • https://greenbins.ca/ckfinder/userfiles/files/82709858598.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/161588a5d07f95---donusazugitu.pdfIn PDF document text
    • https://confidence-ist.com/ckfinder/userfiles/files/jebirojosobibubexaberej.pdfIn PDF document text
    • http://sin-hua.org/userfiles/potirigerataluleburit.pdfIn PDF document text
    • https://unibel.pl/pliki/upload/file/rutugiwufek.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/161538921413fa---94969667588.pdfIn PDF document text
    • http://puginternational.com/ckfinder/userfiles/files/9338340863.pdfIn PDF document text
    • https://jahanchart.ir/data/files/file/77830213332.pdfIn PDF document text
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613743ba5b6e0---jutebanijepitaw.pdfIn PDF document text
    • http://hunting.kg/userfiles/file/vidumaregujasikanatal.pdfIn PDF document text
    • http://chipmax.in/chipmax/ckfinder/userfiles/files/78365997174.pdfIn PDF document text
    • https://osakaav.com/userfiles/files/996403894.pdfIn PDF document text
    • http://rapabzenec.cz/obrazky/files/rinusirixurivige.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/16133dcb9c6059---xorukodobafidabefu.pdfIn PDF document text
    • http://bhavalaya.org/ckfinder/userfiles/files/79968711472.pdfIn PDF document text
    • http://restaurant-lyons.fr/userfiles/file/32767313988.pdfIn PDF document text
    • https://decisionstogo.com/fck_image/file/61663292914.pdfIn PDF document text
    • https://www.iieng.org/editor/ckfinder/userfiles/files/66745970924.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=shannon+wong+mdPDF 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_off0000acd1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xACD1 10220 bytes
SHA-256: e73dd09a3e75c0a05dac7b9e2ad0444e266524b0d3f97961315d4b48f42c6eae
font_01_sfnt_off0000c358.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC358 16268 bytes
SHA-256: 049e0f989fda3822d76f38b84668964db94e27e35b28da2eb26036203198c46f
font_02_sfnt_off0000ec8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC8D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1