Malicious PDF — malware analysis report

Static analysis result for SHA-256 2337f1b3d3cac0c3…

MALICIOUS

PDF

79.7 KB Created: 2021-09-21 05:50:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 359f5b4fadc480efdd7d7047366a0775 SHA-1: 2b74c616de2c3891a22248543b5026d951b14491 SHA-256: 2337f1b3d3cac0c3658c574428334752c8e2523c2e8e92def072fdbc611c3b69
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that point to various domains, many of which are identified as link farms on compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 https://allytemp.ru/uplcv?utm_term=how+to+install+apk+files+on+android+tablet PDF link annotation
    • https://truongthanhco.vn/webroot/img/files/zunoteviwenodofurel.pdfIn PDF document text
    • https://woodfur.in/userfiles/file/19064356054.pdfIn PDF document text
    • https://fishuntpesca.it/file/nirujavu.pdfIn PDF document text
    • http://project-lovcen.me/userfiles/file/zafikurizo.pdfIn PDF document text
    • http://kieryk.pl/img/userfiles/file/95182573787.pdfIn PDF document text
    • http://gomientrung.vn/uploads/image/files/8051654096.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149208cd627d---49118222490.pdfIn PDF document text
    • http://pickup-ws.com/userfiles/files/kinawimazowit.pdfIn PDF document text
    • http://www.primariasantana.ro/uploads/file/44626687770.pdfIn PDF document text
    • https://shevtsov-art.com/uploads/files/33959869433.pdfIn PDF document text
    • http://eg-connect.com/php_codes/Scott/VieauAssociates/code/userfiles/file/rowiguvitofigaxito.pdfIn PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/fe9hb7875evnaiqd1u8gol9pq0/55338717525.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/161334f1b1ac17---89362800529.pdfIn PDF document text
    • http://sladkiy-ostrov.ru/userfiles/files/lavezuboradetisu.pdfIn PDF document text
    • http://www.mbk-montage.nl/ckfinder/userfiles/files/54962784143.pdfIn PDF document text
    • http://schuetzenfest-hemeringen.de/ablage/userfiles/files/62000237331.pdfIn PDF document text
    • http://riph.pl/userfiles/file/kewufiwowalisaw.pdfIn PDF document text
    • https://arhometutor.com/userfiles/file/diwalijesemoralogofijuwiv.pdfIn PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1614049852757b---tabare.pdfIn PDF document text
    • http://fuku-zou.com/userfiles/file/2156188788.pdfIn PDF document text
    • 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_off0000d0bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0BD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e8d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8D4 10800 bytes
SHA-256: 1d4ed86988c36979f6a60486c3ad480a33afe244d3d1958f2d60879494c49f29
font_02_sfnt_off000101a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101A0 18476 bytes
SHA-256: 735e91605cd3bb21aa863461fdfb8f18b1d90c98b296f814fe4641c630c65fc3