Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bda38ccb14fa700…

MALICIOUS

PDF

78.8 KB Created: 2021-09-03 01:01:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: d9a4837516d0ce5426e90f2c66e78596 SHA-1: d82fa1a0f756d88a9c93bd4b30c6ce0d691d8fa6 SHA-256: 8bda38ccb14fa700b0bb9cb959a4c0fdd849cd06fce828d46f769250394cc336
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm with numerous URLs pointing to various domains, many of which appear to be compromised or disposable hosting. The ML classifier strongly indicated maliciousness, and the structure suggests an attempt to manipulate search engine results or redirect users to potentially harmful content. No scripts were extracted, but the PDF structure itself is indicative of a malicious intent to distribute links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 5

  • 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://taiwanglassgroup.cn/userfiles/file/97611265118.pdf In PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/31bf54778e27949ee5fdb1a03dfa5572/82159649277.pdfIn PDF document text
    • http://topenglish.sk/app/webroot/gallery/files/nevodabexufup.pdfIn PDF document text
    • http://p-jtech.com/userData/board/file/morevojobefobulawidu.pdfIn PDF document text
    • http://www.tiendadelbordado.com/ckfinder/userfiles/files/purukonireguwadiboxul.pdfIn PDF document text
    • https://sapsda.org/SapmaUserfiles/file/22514464573.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a98e5885f1---8192460528.pdfIn PDF document text
    • http://ahxxzx.com/userfiles/202104/file/nowavipamuguwakarem.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/sutuzadejibiguvodolug.pdfIn PDF document text
    • http://planet-for-events.de/userfiles/file/56283177513.pdfIn PDF document text
    • https://babetravelling.com/ckfinder/userfiles2/files/49581688010.pdfIn PDF document text
    • https://astefin.ro/ckfinder/userfiles/files/58763489484.pdfIn PDF document text
    • https://laser123.com/geektic/files/mojukit.pdfIn PDF document text
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/a56e33ca9eda5b90d7561dd8bcad0f3c/25622340358.pdfIn PDF document text
    • https://flylights.pl/wp-content/plugins/super-forms/uploads/php/files/9an14p792ido4kkoaoecujb1ai/bajalofegeburezuf.pdfIn PDF document text
    • http://billagelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/72980694951.pdfIn PDF document text
    • http://cambridgekapurthala.com/damana/userfiles/file/19890774535.pdfIn PDF document text
    • https://autoschiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160be45dbb6ec9---68129312681.pdfIn PDF document text
    • https://www.infrascale.com/wp-content/plugins/super-forms/uploads/php/files/de1580d3402ecf9a13f56a1a7ca13724/natagitaragelu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=life+insurance+journal+articles+pdfPDF 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_off0000ce24.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE24 17936 bytes
SHA-256: f595772d6c560ad130063710cc411db516c8a69f54268f5fc5bb3d87170c51c3
font_01_sfnt_off0000fcfc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCFC 10800 bytes
SHA-256: 7cae52d9e4ad518e1ca4422fa42dbc6934f8a7ccc9ac406b566969d9a687d87c
font_02_sfnt_off000115f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x115F3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1