Malicious PDF — malware analysis report

Static analysis result for SHA-256 cbd87a2f10a2f76f…

MALICIOUS

PDF

74.5 KB Created: 2021-06-30 03:22:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 283e0b5ab22ec7e9c45ad293b4163a49 SHA-1: c06880d2a6a6288e0c86b0665caaff9d88b7fb51 SHA-256: cbd87a2f10a2f76fd001405d5d10c3c072a4b83002a1ffd4b3dea719c78c3568
96 Risk Score

Malware Insights

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

The PDF file contains a large number of external URIs, many of which point to compromised WordPress sites. These links are likely intended to redirect users to malicious content or phishing pages. The ML classifier strongly indicated maliciousness, supporting the assessment of a link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://laborke.ru/uplcv?utm_term=what+does+bubba+mean PDF link annotation
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c16b169d167---sarefusuvezisi.pdfIn PDF document text
    • https://kodeac.com/wp-content/plugins/super-forms/uploads/php/files/clh0e8bbdfle7k33knr13nho9c/29491076753.pdfIn PDF document text
    • http://iamsoldierfit.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3de4900d16---52479754134.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/160d467e93af9f---61450643010.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/qnlv4mnjgfaeu0n6ttbt2m1abb/risupejupidapafoziti.pdfIn PDF document text
    • https://ahi.com.ua/wp-content/plugins/super-forms/uploads/php/files/605d115c1984b39d3d9cd3dcbea67fff/5085482388.pdfIn PDF document text
    • http://highendschmiede.de/highendfiles/file/tademogeginune.pdfIn PDF document text
    • https://canadianrelocation.net/wp-content/plugins/formcraft/file-upload/server/content/files/16087624232694---kababibozulizeluf.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/5718ff8d2b6deb9029514e68d8a23680/fuzeragenarilip.pdfIn PDF document text
    • http://uniondeautoescuelas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095dfbc6d411---wagilanudibimusukizefi.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160b5e6a1d8e7c---46509635522.pdfIn PDF document text
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c5130431a5d---welulilufavepel.pdfIn PDF document text
    • https://kantankacreative.com/wp-content/plugins/super-forms/uploads/php/files/421faec2544c3ed91dc83f2b8894c5c7/tugoritojob.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606f152210a44---34236316149.pdfIn PDF document text
    • http://mattstergamer.com/wp-content/plugins/super-forms/uploads/php/files/eaeevql0c1tc0sbs1q3b5mpeej/lunebatetonomifa.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/1607016d889c43---nasemino.pdfIn PDF document text
    • https://space1500.com/wp-content/plugins/super-forms/uploads/php/files/3552befbc3802a85f9fcec6b859c2292/tefusupojede.pdfIn PDF document text
    • http://eko-inwest.eu/upload/file/64060664562.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/814a7518342611c90db9bf1be607e12f/4077777805.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/840p4akocjst0knvh24fsb70j9/xarugidililopemuzuxu.pdfIn PDF document text
    • https://np21bellapalermoshopping.it/file/88167709650.pdfIn PDF document text
    • https://mercedesmazo.es/wp-content/plugins/formcraft/file-upload/server/content/files/160a38be111b5d---dexedakonape.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_off0000c14b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC14B 10508 bytes
SHA-256: b39b5bc2654ca41226bde3952e475c705f49798efdd9436a48da4e39c60ce5cb
font_01_sfnt_off0000d90a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD90A 16892 bytes
SHA-256: 51897d600c7d140bd597abed6cbe4b5650ccd9bf5a5222c98471fbb8cfa00816
font_02_sfnt_off0001052a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1052A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1