Malicious PDF — malware analysis report

Static analysis result for SHA-256 f271b37b9aadb13c…

MALICIOUS

PDF

70.8 KB Created: 2021-09-30 16:46:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: accbb0cfea37dd3b869bb90bcb1aaa3c SHA-1: 565a252fe49241e918941241288b3b3f8ca117d4 SHA-256: f271b37b9aadb13ca1a5246ef5434afedac303c49d135b11c46e98cd681b42b8
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external links, many pointing to compromised WordPress sites or disposable hosting. The ML classifier strongly indicates maliciousness. The embedded JavaScript likely facilitates the redirection to these malicious sites, which are designed to host further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

Heuristics 6

  • 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 https://szallas-karpatalja.com/upload/7799248380.pdf In PDF document text
    • http://appextskihjthj.handysociality.com/upload/files/vokusatofotefokirubani.pdfIn PDF document text
    • http://geodez.com/pliki/file/zanadalodujemi.pdfIn PDF document text
    • http://milkexim.ru/imgeditor/file/21732278593.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1615355e156158---11794965180.pdfIn PDF document text
    • https://strongpointmarketing.net/userfiles/file/40553546908.pdfIn PDF document text
    • http://iweldbot.com/ckfinder/pho/files/96424603088.pdfIn PDF document text
    • http://vdavloeren.be/userfiles/files/14551210909.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613e00a6b225e---jogefikesosorenota.pdfIn PDF document text
    • http://dywin.com/uploadfile/files/sepux.pdfIn PDF document text
    • http://tokstar.com/_UploadFile/Images/file/lejitun.pdfIn PDF document text
    • http://ser-buk.com/userfiles/file/xakodoru.pdfIn PDF document text
    • http://www.firengo.com/userfiles/files/82175867104.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/996ccb804e9dc50baf33c781ec5a8dc9/xalivoxobakesunoxuju.pdfIn PDF document text
    • https://cli-kh.com/uploads/files/202109301701413276.pdfIn PDF document text
    • http://offerparts.com/upload/files/95197808753.pdfIn PDF document text
    • http://skyrun-arser.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/210918205821994792xx7a09.pdfIn PDF document text
    • http://yummyschool.com/_UploadFile/Images/file/93522863284.pdfIn PDF document text
    • http://redigonda.it/userfiles/files/96151024712.pdfIn PDF document text
    • http://samarthservice.com/userfiles/file/79827970444.pdfIn PDF document text
    • https://ikuseikyokai.jp/ckmedia/files/48797381430.pdfIn PDF document text
    • https://www.retake.dk/ckfinder/userfiles/files/80089436894.pdfIn PDF document text
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147b9a8b6e4d---37774204093.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=android+sound+mp3PDF 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_off0000b005.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB005 10368 bytes
SHA-256: afea0ae17aca36974f68c4638f22f60d6f952fa19008de537a5e707056abbcb6
font_01_sfnt_off0000c760.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC760 18768 bytes
SHA-256: 190be716743cc31d5aed89e648a87c3dfe7246abb99c75736f463aa1f980e9d6
font_02_sfnt_off0000f605.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF605 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1