Malicious PDF — malware analysis report

Static analysis result for SHA-256 8da45c33dcd0a4ea…

MALICIOUS

PDF

91.8 KB Created: 2021-10-12 19:25:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: a88278d2e587ca08def2ff29d50943bd SHA-1: 659c8812912edea90f53af4d1b82e43402ca96a3 SHA-256: 8da45c33dcd0a4ea2792d79b2232ddb6de92c71dca46b8e7a0947775c7c14619
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external URIs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed for phishing or malware distribution. The ML classifier and ClamAV detection strongly support its malicious nature. The embedded JavaScript likely facilitates the redirection or payload delivery, contributing to the overall phishing attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://btsoft.vn/uploads/files/jadekejesowuwozegowet.pdf In PDF document text
    • http://riverla.vn/uploads/userfiles/file/57688816904.pdfIn PDF document text
    • https://maxtarget.by/ckfinder/userfiles/files/37089316813.pdfIn PDF document text
    • https://thaibamboorestaurant.ca/phpsites/bard_ford/uploads/file/69420254313.pdfIn PDF document text
    • http://carshopm.com/js/upload/files/92590504043.pdfIn PDF document text
    • https://xnkvinatimex.com/uploads/files/53781756288.pdfIn PDF document text
    • http://pjzhengwang.com/upload/file/20210906_043555_191.pdfIn PDF document text
    • http://dentalweek.eu/userfiles/files/25429868833.pdfIn PDF document text
    • https://greshamgilessalon.com/wp-content/plugins/super-forms/uploads/php/files/c7d228933efe85d473887578c1d7240f/35377381317.pdfIn PDF document text
    • http://trustycctv.com/ckfinder/userfiles/files/81957063061.pdfIn PDF document text
    • https://meesens.be/KrMee/Tekstverwerker/70689450281.pdfIn PDF document text
    • http://bannermaul.com/userData/board/file/36528238903.pdfIn PDF document text
    • http://p-jtech.com/userData/board/file/83274850900.pdfIn PDF document text
    • http://camel-republic.com/media/userfiles/files/kalarulo.pdfIn PDF document text
    • https://silverlabpupsforsale.com/userfiles/files/24344130242.pdfIn PDF document text
    • https://tenhucchi.com/upload/files/27536116826.pdfIn PDF document text
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/341475fb2bb6c589e3d506a347eff856/bolavuj.pdfIn PDF document text
    • https://ppuhperspektywa.pl/files/edytor/file/54407086502.pdfIn PDF document text
    • http://havefuntogether.com/image/upload/File/wilexuve.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/2b6b30d8bc1ff1fb6a58dd4af1588324/zejibesekizux.pdfIn PDF document text
    • http://transbur.ru/admin/ckfinder/userfiles/files/litaranitojorimer.pdfIn PDF document text
    • http://abdon.madteam.net/ckfinder/userfiles/files/654866203.pdfIn PDF document text
    • http://chipgene.com/image/files/20210903_081004.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Gsjc/~3/23D8k0Ec_6w/uplcv?utm_term=white+vaginal+discharge+in+dogsPDF 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_off0000fae0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAE0 10708 bytes
SHA-256: c33cfe50f5fd4ddc71d0378aa143cea45e05e227f1389d8b4be866d6fc2e9988
font_01_sfnt_off00011335.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11335 19800 bytes
SHA-256: df91ecae2b23cd2c386e3ab22d859ec75c34298af1d78f60c64bf130a1506708
font_02_sfnt_off000147a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x147A1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1