Malicious PDF — malware analysis report

Static analysis result for SHA-256 5a64064e755c2d8d…

MALICIOUS

PDF

79.9 KB Created: 2021-09-19 19:23:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e9cc9b871e7270fa07670d31ef44bcef SHA-1: b7d134ce5406bb1af467a589702ddcafd5253c49 SHA-256: 5a64064e755c2d8d1a0c99ce77bf6909a6d9dedcaf5942464c91564f50ca0398
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to compromised WordPress sites and other domains, identified as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery through these links. The document body is unreadable, but the heuristics and URLs confirm a pattern of directing users to potentially harmful external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://smidgel.ru/uplcv?utm_term=emoji+samsung+vs+apple
    • http://ourgans.org/userfiles/files/kebusasizetugabasifakexa.pdf
    • http://mistral-paints.cz/userfiles/files/birapomirakizawej.pdf
    • http://denge.aero/upload/files/werizazarexuzenuku.pdf
    • http://nbmounts.com/userfiles/file/1631766054.pdf
    • https://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/e91bb589728fcea0b4a2a612bf911a29/16809046732.pdf
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/e300642204898a8eba434832cd51e934/durikeko.pdf
    • http://creatinglifeoptions.com/userfiles/files/lujivifazetelabixubib.pdf
    • http://tolaniprojects.com/userfiles/file/85690267898.pdf
    • https://doanhnghiepvietnam.niengiamdoanhnghiep.vn/img_duhoc/files/dapuvixurizewuriw.pdf
    • https://laps.pl/userfiles/file/zotetosofoku.pdf
    • http://abwmechanicsville.com/uploads/files/38365378442.pdf
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1613175dd0aecd---85674788788.pdf
    • http://garantc.ru/userfiles/file/28597747233.pdf
    • http://mptech.vn/ckfinder/userfiles/files/28704998237.pdf
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/f1j00nv5iimri42kdqq1tmo4gn/15900431856.pdf
    • http://qiuyutv.com/userfiles/files/20210919040038.pdf
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161350267946c8---josazek.pdf
    • http://jeanthompson.nl/ckfinder/userfiles/files/punugevofinep.pdf
    • http://videlec.be/ressource/file/susob.pdf
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/6e473eb062372fc151b0bd1f9c215615/rumolazumokunizopo.pdf
    • https://e-ceramika.pl/userfiles/file/pulavaxiwumulidefojarus.pdf
    • http://aftp.bg/userfiles/file/texezebemulejo.pdf
    • http://mega-treid.com/userfiles/files/nonedizema.pdf
    • http://dc-a0dcf319a153.breakthroughsport.com/userfiles/files/9357850987.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d62b.bin
91fd9621cc9ff1397e84c1e0a8c238fa1b37f16f47aef6f6f5d786f7d2568473
pdf-font-stream PDF embedded font (sfnt) at offset 0xD62B 16908 bytes
font_01_sfnt_off000101ce.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x101CE 16792 bytes
font_02_sfnt_off000119e5.bin
32cbec9a0b0df83294f5ead374b7559a21076d1c8b782d0f74c2e16d0bda50c8
pdf-font-stream PDF embedded font (sfnt) at offset 0x119E5 10676 bytes