Malicious PDF — malware analysis report

Static analysis result for SHA-256 d905bf274f75d54f…

MALICIOUS

PDF

91.3 KB Created: 2021-09-18 13:05:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 5daefe214c8256bb3955faab6fd31a6b SHA-1: b48c0462debb68c70c923480137803c28a4122a8 SHA-256: d905bf274f75d54f62218f854b98a40246b4e616e8d3159f41b1edac15e33b21
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or are hosted on disposable domains, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the structure and URL patterns suggest an attempt to lure users to external sites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://allytemp.ru/uplcv?utm_term=instagram+free+like+apk PDF link annotation
    • http://bigcool.net/webroot/img/files/69288954273.pdfIn PDF document text
    • http://gemculture.com/userfiles/file/vuvasiwotoxuboxosu.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/161443ca9cc04c---wijevobexisotuz.pdfIn PDF document text
    • http://insfilings.com/skyzone_classic/upload/files/jugenufapi.pdfIn PDF document text
    • http://villacappuccina.com/userfiles/files/nejexejidelu.pdfIn PDF document text
    • http://elitacasa.it/images/file/37597087392.pdfIn PDF document text
    • https://nnkcreations.com/userfiles/file/dimubotumofizopet.pdfIn PDF document text
    • http://sonnenheizung.ch/fckeditor/editor/images/file/4984022182.pdfIn PDF document text
    • https://www.truck-transport.com/ckfinder/userfiles/files/givimerinutikes.pdfIn PDF document text
    • https://francemonde.news/UserFiles/file/rapud.pdfIn PDF document text
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613adf3364c7a---60816197807.pdfIn PDF document text
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/55291e9b50e114f4f09dbf6b3fadc168/sunapotixiwumovenefeko.pdfIn PDF document text
    • http://remontnoedelo.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16133c0b87a0f4---sakosod.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/kuu6ou3a6cnpqjnleqisq33924/govow.pdfIn PDF document text
    • http://alpinedelhi.com/userfiles/files/92257477989.pdfIn PDF document text
    • http://dh-life.com/ckfinder/userfiles/files/paderevezumuneru.pdfIn PDF document text
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614258772d52e---vududalobofiwufotiwi.pdfIn PDF document text
    • http://pnc21.com/files/fckeditor/file/275131128613a74dd74c63.pdfIn PDF document text
    • http://mail-ex.net/userfiles/file/topiperesokufosirolus.pdfIn PDF document text
    • http://cokhilegia.com/upload/files/53249299301.pdfIn PDF document text
    • https://hondaotohaiphong.vn/upload/files/71627144150.pdfIn PDF document text
    • http://geoodwierty.pl/files/file/66928909278.pdfIn PDF document text
    • http://shinaval.ru/userfiles/file/pefovoxanimu.pdfIn PDF document text
    • 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_off0001008d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1008D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000118a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118A4 10624 bytes
SHA-256: 4d95e97b948c2ff1ef744f12dad12b14600d586f3bf72cca0b9d0881dda6ddb4
font_02_sfnt_off000130e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x130E2 18252 bytes
SHA-256: 238f1b6b89f005f376f529584d06967677dc66b1f5b97a14d8015282d3f99733