Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff43061beeb75342…

MALICIOUS

PDF

85.6 KB Created: 2021-09-14 12:48:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 9b8a20fd0ca5470b92f89af40eb30377 SHA-1: 5c03a0bb475ea74e97d603ed2c37b2563e35a29b SHA-256: ff43061beeb75342f561c281511cad697ba9fbdc583e4c4508172e516acb9011
96 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites and disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier strongly flagged this PDF as malicious. The embedded URLs, while some are marked benign, are part of a larger pattern of suspicious link distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 https://abofahed.com/userfiles/file/97548179237.pdf In PDF document text
    • https://vietrocknet.org/app/webroot/img/files/28939637415.pdfIn PDF document text
    • http://go-trec.com/wp-content/plugins/super-forms/uploads/php/files/f6lf381qk46c2mj1sfbd2e76tm/79641107618.pdfIn PDF document text
    • https://laurallo.com/ckfinder/userfiles/files/najuzudo.pdfIn PDF document text
    • http://phyllisrubensteinlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/98982986817.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/161393f37f1eea---88937483454.pdfIn PDF document text
    • https://akemi.ro/hirek/file/91717296930.pdfIn PDF document text
    • http://www.ciesol.es/ckfinder/userfiles/files/tepelaje.pdfIn PDF document text
    • https://frisch.ro/files/file/88815157526.pdfIn PDF document text
    • http://sportingclubalbinia.eu/userfiles/files/55836123070.pdfIn PDF document text
    • https://perfecthospitals.org/ckfinder/userfiles/files/39249901026.pdfIn PDF document text
    • https://atlastoursntravels.com/userfiles/file/45162636524.pdfIn PDF document text
    • http://metalzilemboeventi.com/userfiles/files/gavid.pdfIn PDF document text
    • https://akproauto.com/nbloom/fckuploads/file/daxijazus.pdfIn PDF document text
    • http://matsusushionline.com/uploads/files/vujiporofawebesar.pdfIn PDF document text
    • https://dhins.com/testingsites/advantage_aviation/assets/media/file/97842023600.pdfIn PDF document text
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/161320ad5c79d7---tavodikololoxiwewen.pdfIn PDF document text
    • http://ttlh.vn/storage/ckfinder/files/84541355928.pdfIn PDF document text
    • http://wxeina.com/userfiles/files/rewofikalog.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133ab331aeb6---35225115522.pdfIn PDF document text
    • https://montpellier-business-plan.com/mbp/upload/images/images/upload/ckfinder/tubiporuwi.pdfIn PDF document text
    • http://quatanggiabao.com/images/uploads/files/jatelisupuzijewaxisiroge.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=how+to+reset+my+pattern+lockPDF 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_off0000e9d7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9D7 10724 bytes
SHA-256: f9eaa524b288efbb1acd7d78918e98587f744ba697ac013cf0e4c7c2862cd080
font_01_sfnt_off00010294.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10294 17872 bytes
SHA-256: 3501c5d5e007dba73d170272a9fd7022cf0a866256477bb08e1ba6ebd2bb12cb
font_02_sfnt_off000130d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130D4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1