Malicious PDF — malware analysis report

Static analysis result for SHA-256 8758b33ba9156d7a…

MALICIOUS

PDF

84.1 KB Created: 2021-07-16 02:28:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 75a00348275bd455a7dcc050313f44df SHA-1: 98e4508c05f4e93fab8da6c7a20b49ac36a3f4fd SHA-256: 8758b33ba9156d7a546471e1ac5b2b059c73849c5443f3991b51a152f25d8631
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous links, many pointing to compromised WordPress sites, indicating an attempt to redirect users to malicious content. The ML classifier strongly flagged this PDF as malicious, and the heuristic findings suggest it functions as a link farm designed to distribute further payloads or phish for information. The embedded JavaScript is likely used to facilitate these redirects.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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 http://munnarinfo.in/userfiles/file/lomisumesapaz.pdf
    • http://aprendanow.com/wp-content/plugins/super-forms/uploads/php/files/9760ae9290c759f4fa7d0ae440d05958/13760562579.pdf
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b0950bbf558---toroj.pdf
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a63dd606ec7---1571076852.pdf
    • http://mvhs1964.com/clients/2/20/2030ff4f331b14c2016b95997514b7ac/File/sozezelurul.pdf
    • https://ekransamara.ru/files/73915531501.pdf
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/004f1a3a845d5e7bb60ae39f81da8c43/viwiletavejigisugug.pdf
    • http://seoulsquare.com/userfiles/file/zizimud.pdf
    • http://pescepiana.eu/userfiles/files/18563704535.pdf
    • http://energo-winstal.pl/userfiles/file/7657200301.pdf
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/495126960799699610a2854e992e0e5e/zexifedoridipobax.pdf
    • http://alexanderjamesbackcatalogue.com/userfiles/file/bibozikipinifuja.pdf
    • http://quickvideo.nl/userfiles/file/74956926502.pdf
    • http://www.martiusstaden.org.br/js/ckfinder/userfiles/files/9249090639.pdf
    • http://www.vegagastro.pl/upload/file/42172968423.pdf
    • http://ellev.fr/upload/files/diveritamalobipulujixedas.pdf
    • http://ketoanantamhcm.com/uploads/files/ranetujepomaresi.pdf
    • http://woodwork.pl/ubezpiecz/obrazy/file/20435035853.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608333123fbf9---64470618988.pdf
    • http://kaupa.cz/userfiles/file/sosuwidetot.pdf
    • https://www.asahinafunnels.com/wp-content/plugins/super-forms/uploads/php/files/0322dj1oi6qcpr9pergrtf3th0/37200228737.pdf
    • https://bestofbucerias.com/upload/file/992205157.pdf
    • http://berbun.com/user_img/file/doralujifasonu.pdf
    • http://ipvoicenj.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082b5bfc05b6---77392618841.pdf
    • http://aiswaryamatrimonials.com/fck_uploads/file/94513196917.pdf
    • http://gdgom.com/upload/file/210701040759602648n3rfxvo7p7kt.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=stranger+things+toxicwap
    • 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_off0000e45c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE45C 16792 bytes
font_01_sfnt_off0000fc6e.bin
572ae654e7d9d4016bf21c86adeeaea475f951f649491cd19fc592f456a23e54
pdf-font-stream PDF embedded font (sfnt) at offset 0xFC6E 17340 bytes
font_02_sfnt_off000129f7.bin
7039724a5103da3d16877bc2432bdf86cc750a9501973b45748eb4bef81a20db
pdf-font-stream PDF embedded font (sfnt) at offset 0x129F7 10868 bytes