Malicious PDF — malware analysis report

Static analysis result for SHA-256 6ccf3631b6426c71…

MALICIOUS

PDF

90.2 KB Created: 2021-07-02 03:42:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 116548a380948563182e65883b980106 SHA-1: 92b65ac1cd8e914c989c157e20d81ba3b4357788 SHA-256: 6ccf3631b6426c7103a810205a71997798c04e43f0a40b9e4b764ac971c1b8b8
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to compromised websites, suggesting it is part of a link farm designed to redirect users to malicious content. The ML classifier strongly indicated maliciousness, and the presence of multiple external URIs and compromised CMS upload links supports this assessment. No scripts were extracted, but the overall structure points to a phishing or malware distribution lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9924

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://crewmak.ru/uplcv?utm_term=circles+class+9+questions+with+solutions PDF link annotation
    • https://ddshower.com/ckfinder/userfiles/files/borotuxidebebe.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/5d8d33917629e38c94a3819ff171854b/39505657766.pdfIn PDF document text
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/160acaf175aef5---59248406307.pdfIn PDF document text
    • http://lbs.ac.at/wp-content/plugins/super-forms/uploads/php/files/rh62qrd2assp24thliovah9t8r/50578712784.pdfIn PDF document text
    • http://www.microsinusectomi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073a1e63ab80---19019000049.pdfIn PDF document text
    • http://avtrak.ru/ckfinder/userfiles/files/53893865679.pdfIn PDF document text
    • https://toromecanicorodeo.com/files/naparijonumujulebavavaled.pdfIn PDF document text
    • https://growlocals.com/wp-content/plugins/super-forms/uploads/php/files/4607243d64c8fafff2a480af0bb9c38b/sopetijukitujibesi.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c7b14d40353---73950039901.pdfIn PDF document text
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/fc87488737a3accbd4bc24449723a5c4/wuzasikivawadabivexar.pdfIn PDF document text
    • https://acronimocostanzo.com/userfiles/file/birejevopemo.pdfIn PDF document text
    • http://szpk.hu/_user/file/niwilagekoniropuf.pdfIn PDF document text
    • https://gauravkankariya.com/wp-content/plugins/super-forms/uploads/php/files/amhellkvjqfc559523trmoa5f3/natifeguranalimubogo.pdfIn PDF document text
    • http://hk-dcc.com/wp-content/plugins/super-forms/uploads/php/files/rn5u7d61l8ea96ivhu226fh17g/gexupa.pdfIn PDF document text
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/04d1b4da11b9c0c2e602e0a3628d375e/vatusadegategomameva.pdfIn PDF document text
    • https://jamiatulbanat.in/wp-content/plugins/formcraft/file-upload/server/content/files/1606d45fd90941---benogexelipoxumewomikewex.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160aeb19d6cbb5---ginuge.pdfIn PDF document text
    • http://fcv-bo.org/data/fcv-bo/userfiles/file/76619431703.pdfIn PDF document text
    • http://hublihorse.com/uploads/userfiles/files/farefomoxiwul.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/035c4799e5dfee79313e548e58577116/fijofuxutunixaruve.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/92f4f3060e163b414f1283d1c613c7a9/xegepawogamofor.pdfIn PDF document text
    • http://pcmcpropertyblog.com/wp-content/plugins/super-forms/uploads/php/files/da9d796a8d5910656c48ed3382212443/73416556973.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/jus898gitit5eqoce3n6esfrn1/30143333168.pdfIn PDF document text
    • http://bestapp4u.com/admin/uploadedfiles/file/12606698004.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e59d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE59D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fdb4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDB4 10860 bytes
SHA-256: 5e06cfc42011f2ad30fe34fd6e672037021e3e23c0a26e6a8695f2bd6094739e
font_02_sfnt_off000116d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116D8 17484 bytes
SHA-256: 68bd856aca8594615da4bf723ff8501a0076a538df113ef564e13b608ea41f39
font_03_sfnt_off00014502.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14502 16224 bytes
SHA-256: d1ff55f592c4bcea43ccd85b360c3187e32f6098a5c2e755fcb085bc62ff939f