Malicious PDF — malware analysis report

Static analysis result for SHA-256 c93cf87a579d6334…

MALICIOUS

PDF

89.8 KB Created: 2021-07-31 17:16:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 629eb88b5f623dc6c3b379d0d7ebf95f SHA-1: 6f8873bee3d745ea98e2f3243a106fecd0e73e83 SHA-256: c93cf87a579d633409ece1bfa4bd4b540be5e287bbc9124394deaffafb801bf6
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a link farm or phishing campaign. The ML classifier strongly indicates maliciousness, and the presence of embedded URLs points towards an attempt to redirect users to potentially harmful sites. No scripts were extracted, but the overall structure and URL patterns are indicative of a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://archism.ru/uplcv?utm_term=how+to+read+a+chest+x-ray
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/2edfktp04j6kss8r60ml5rauro/kenonanin.pdf
    • https://takiminsahada.com/wp-content/plugins/super-forms/uploads/php/files/rv5thtk2kcpfdjmcu4jmcp3635/69745269093.pdf
    • https://avenue102.com/uploads/file/69470933766.pdf
    • http://www.anjhimayath.com/upload/file/menawud.pdf
    • http://arohitourandtravels.com/userfiles/file/6840960133.pdf
    • http://lempreintedubois.fr/userfiles/lempreintedubois.fr/file/kuzuzefubobisiso.pdf
    • http://jilienjrubin.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/pidivorowefofoxagama.pdf
    • http://weberstellen.ch/userfiles/file/kefigamewixotetedevere.pdf
    • https://datajournonepal.org/files/40708652892.pdf
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160fcf890af704---3068686425.pdf
    • https://fundacionamigosdelmarcaribe.ong/ckfinder/userfiles/files/9003693438.pdf
    • http://www.retorika-zidar.si/ckfinder/ckeditor_uploaded_files/files/paboxinalonodigukape.pdf
    • https://burgas-remonti.com/userfiles/file/rupikotedij.pdf
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160833a2373341---81407219005.pdf
    • http://akkoryazilim.com/userfiles/file/fewujul.pdf
    • https://toptenstudy.com/upload/files/BodyFile__60EE6D5873BDB.pdf
    • http://forresterfamilyreunion.com/clients/c/cc/cc72bfd2512333311cc1ef5a4fdef90f/File/15160249313.pdf
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d1684fa83cae851bef050fe2b28adaf5/jomariwasatumo.pdf
    • https://bykevin.com/wp-content/plugins/super-forms/uploads/php/files/8022941a1ebb82b5d53c04124899ba1d/27892852411.pdf
    • https://www.areatransfers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f1a29565d9e---60049524966.pdf
    • https://pk-kuepfer.ch/ckfinder/userfiles/files/kefedexi.pdf
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/6302d6c032daad24b29abd04e376a359/92869877384.pdf
    • https://alubiasdetolosa.com/files/galeria/files/65868838969.pdf
    • http://irodori.kir.jp/files/file/mugasel.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_off0000f9f3.bin
2bfe15964355487440a310e3ea5943bbf3b167fa2c302ad6a9cd05955205f59c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9F3 10552 bytes
font_01_sfnt_off00011242.bin
1c29c17bc90d0b74b9f9d0d7cf6f0666d5db908d11733d3b7e7245fe76297915
pdf-font-stream PDF embedded font (sfnt) at offset 0x11242 17140 bytes
font_02_sfnt_off00013efe.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13EFE 16792 bytes