Malicious PDF — malware analysis report

Static analysis result for SHA-256 e31d9db0c52ff89a…

MALICIOUS

PDF

79.6 KB Created: 2021-09-10 14:09:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: e291106662b50e07ebe94bcfd7b65046 SHA-1: 2f0824bcec0025758bef228cf78f4d7a17f06160 SHA-256: e31d9db0c52ff89a0ecd3746a8ee9a8d7a9680923abc17b7659e1d9152395b97
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. Heuristics indicate the document functions as a link farm, directing users to multiple external websites, some of which are hosted on compromised CMS uploads or disposable domains. The presence of numerous external URIs suggests an attempt to lead users to phishing sites or download further malicious content.

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://hakasasi.id/userfiles/file/talewagadojez.pdf In PDF document text
    • http://bonaparte-kerkrade.nl/fckeditor/ckfinder/userfiles/file/7499322988.pdfIn PDF document text
    • http://evo-models.com/uploads/userfiles/files/vofofipirologe.pdfIn PDF document text
    • http://aptekadc.pl/userfiles/userfile/lenarurupaj.pdfIn PDF document text
    • http://madurastones.com/userfiles/file/nularaxofotadugiwo.pdfIn PDF document text
    • http://zeminyerkaplama.com/upload/ckfinder/files/ribugawinelesuf.pdfIn PDF document text
    • https://kaptenhoki.com/contents/files/46749027002.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/16131b2d0209e2---44586089737.pdfIn PDF document text
    • http://aquamedia.cn/ckfinder/userfiles/files/bawoze.pdfIn PDF document text
    • http://chrislahoda.ca/userfiles/file/28737488120.pdfIn PDF document text
    • http://ifaistos.reality.gr/~triantaf/images/file/nesozebazejefivofa.pdfIn PDF document text
    • https://marsanz.pl/uploads/fck/file/gelusozasopobolosarefitus.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130ffa2d0810---ruxegokudunetimow.pdfIn PDF document text
    • http://olgapolyakova.de/files/files/4161967695.pdfIn PDF document text
    • https://larrialdiak.es/files/galeria/files/93816905542.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138806cdeee5---28771973396.pdfIn PDF document text
    • http://3qlohas.com/CKEdit/upload/files/kafobikoxisopazigesun.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/eafqhd3mnoa3ef766e8rkgg9gg/44078301586.pdfIn PDF document text
    • http://tobn56.com/UpFiles/file/75291644137.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161348f6e20fcc---30501556949.pdfIn PDF document text
    • http://kursadowicz.pl/Upload/file/ranodabegi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=define+cross+curricularPDF 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_off0000d3a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3A6 10332 bytes
SHA-256: 472785454e45bdab15e08a563fa18cd468c5951de03047e429eecda90fe921cd
font_01_sfnt_off0000eb13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB13 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010325.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10325 17688 bytes
SHA-256: 3998ecbd6520653011ae9b9eddd019ef5adb1ad4c5202e0f3c56d6c8d6743825