Malicious PDF — malware analysis report

Static analysis result for SHA-256 71333f8c78803076…

MALICIOUS

PDF

88.6 KB Created: 2021-07-08 04:23:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 17b56accf882af5841b94412290959e9 SHA-1: a88d18a85a61555670837ef883b25a86fd0d9f85 SHA-256: 71333f8c78803076bdae7fe68b2000786714ae12dda7743d01606c231eed5c45
104 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm for SEO manipulation or to distribute further malicious content. The ML classifier strongly flagged this PDF as malicious, and heuristics indicate it's a link farm designed to lure users with phrases like 'Click here to download'. While no scripts were explicitly extracted, the nature of the URLs and the link farm structure points towards a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://krisoc.ru/uplcv?utm_term=malayalam+new+movie+download+tamilrockers
    • https://theatresaucinema.fr/uploads/file/81425534560.pdf
    • http://archgeo-leszno.pl/uploads/userfiles/files/vamomaxesedibagatejin.pdf
    • http://biblioteka-belzec.pl/upload/files/46835115183.pdf
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/rjhia6fqedrdq8uknbjqgknlrn/nisuvudotugiwijopux.pdf
    • https://www.deuba.info/wp-content/plugins/super-forms/uploads/php/files/v5cacr8dbfg5mk3r5is2ev1c0e/297120646.pdf
    • https://btsis.com/upload/ckfinder/files/fenonebixozaduvinijo.pdf
    • https://loctra.net/userfiles/file/nobijujesonesorejusejim.pdf
    • http://jtylek.pl/Upload/file/siburaxozewir.pdf
    • https://thehamptonsbloomington.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608387b5348fa---bipedodopiwulere.pdf
    • http://axiomestates.com/userfiles/file/3021983565.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087f294ae5a1---72169735699.pdf
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/16082ec2a8022a---xezowi.pdf
    • http://xn--om2b25zm6igqb.com/ckupload/files/revumefimeg.pdf
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/dbff5a3249b93750bb8fbea0a5800f15/jipomirilanifutunomizudo.pdf
    • https://www.northernillumination.com/wp-content/plugins/super-forms/uploads/php/files/9170db30848808ca9e98f01fe539f3de/sexirojanike.pdf
    • http://raykingcarroll66.com/clients/2/29/292092747e06e0ab09130fa737b110c0/File/42758785211.pdf
    • http://canxetaianhduc.com/images/file/27589422650.pdf
    • https://juhaszautovill.hu/userfiles/file/dugabi.pdf
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/d3e34074c5ddc2a108d5418204167069/63950893306.pdf
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/o0h0rck83a2t3d0u4ekr9hntd5/jefokanapuxuxoxilekawag.pdf
    • http://weingut-suppan.at/files/73511897677.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_off0000f783.bin
b274212de52979282eccef4929410b7ea13cdb26ebebf73949bdae934230667d
pdf-font-stream PDF embedded font (sfnt) at offset 0xF783 17024 bytes
font_01_sfnt_off000123c2.bin
62609243a9a79d3dde7dd5e6155c79d8da8baab09b949943449bee1ac4d91f75
pdf-font-stream PDF embedded font (sfnt) at offset 0x123C2 10880 bytes
font_02_sfnt_off00013cfb.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13CFB 16792 bytes