Malicious PDF — malware analysis report

Static analysis result for SHA-256 7601b0dd0d84dbdf…

MALICIOUS

PDF

81.9 KB Created: 2021-09-12 18:27:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: bef4f8f54e183941229537d3fdb1b725 SHA-1: 6dfcc83f9f9d6efb9fc3fc41b9d46bda9cab1c66 SHA-256: 7601b0dd0d84dbdfc79171818258623c84a7f533f08d077bb928aa6fc15aca3a
96 Risk Score

Malware Insights

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

The PDF contains a link farm heuristic, indicating it's designed to direct users to multiple external websites. Several URLs point to compromised CMS upload directories, suggesting a pattern of using vulnerable websites for hosting malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://dienmayminhchau.vn/uploads/news_file/lifavuduniku.pdf In PDF document text
    • http://jjw-led.com/userfiles/file/gawibinex.pdfIn PDF document text
    • http://findmecakes.com/userfiles/files/tatazijizexiragifula.pdfIn PDF document text
    • http://strandedtattoo.net/file/8145165116.pdfIn PDF document text
    • http://jplus-ag.com/upload/files/BodyFile__613096B35B63A.pdfIn PDF document text
    • http://ettermanenterprises.com/ckfinder/userfiles/files/15204090386.pdfIn PDF document text
    • http://www.introspekta.si/ckfinder/ckeditor_uploaded_files/files/82946184305.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f70e43e3cb---23131017396.pdfIn PDF document text
    • http://piri-piri.pl/ckfinder/userfiles/files/xifitijuwulominegabapi.pdfIn PDF document text
    • https://detskeihriska.eu/ckfinder/userfiles/files/52605352288.pdfIn PDF document text
    • http://atol-res.pl/uploads/file/mosojokurun.pdfIn PDF document text
    • http://szhlfz.net/upload/19470800383.pdfIn PDF document text
    • http://freetds.net/userfiles/file/25225167173.pdfIn PDF document text
    • http://drapikowski.pl/uploaded/fck_files/file/87338019825.pdfIn PDF document text
    • http://georgewongdesign.com/gwd/upload/files/kegesi.pdfIn PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cb2fce43ba---mogolu.pdfIn PDF document text
    • https://whitesal.com/data/images/file/7349_20210905111524.pdfIn PDF document text
    • http://sourceandsecure.com/uploads/userfiles/file/72920587057.pdfIn PDF document text
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/gtejasl5ntlpoofdgoa4vbr7ce/5264621003.pdfIn PDF document text
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1612e9d5826007---xuwijoxofavixapud.pdfIn PDF document text
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bec6d7fcea---wufojokijexojuserabobaxe.pdfIn PDF document text
    • https://led7.ru/file/87432609648.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=cara+menyembunyikan+tombol+home+di+androidPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d390.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD390 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000eb9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB9D 1732 bytes
SHA-256: 5c6c785476e112a6f75a41f06a02e059cdfb235959dec2f331dec4fc21c5e077
font_02_sfnt_off0000f3da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3DA 10824 bytes
SHA-256: 54cbd81ae7275d6a3d9ab7c90f58b5008c17c70bd93ab4e6796d2cd65cf391ec
font_03_sfnt_off00010c98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C98 16440 bytes
SHA-256: ed5c98a979947aca42f98eba359ab0bcaa46717a969db10beb50c5207c6ca863