Malicious PDF — malware analysis report

Static analysis result for SHA-256 d45a57a5b72a4381…

MALICIOUS

PDF

85.2 KB Created: 2021-07-14 04:37:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: e7d5ee90bf99790377c8496963822329 SHA-1: fa6c3ec741572af06f4eecbf862904e349b8e740 SHA-256: d45a57a5b72a4381b5d682a742f78f38028f8adddb1159e7982ba0fca1c9f010
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to compromised WordPress sites, which in turn host other PDF files. This suggests a link farm designed to redirect users to malicious content, likely for phishing or further malware distribution. The ML classifier strongly indicated maliciousness, supporting this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://chcial.ru/uplcv?utm_term=nursing+outcomes+for+acute+pain PDF link annotation
    • https://razdolle.by/wp-content/plugins/super-forms/uploads/php/files/335ktv3bgumdr3vef0amph69p6/tizokomezuxelubawusidob.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/vozojimazufavijipevap.pdfIn PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3c0cad4e1---jisirefibilirotaxa.pdfIn PDF document text
    • https://www.freshstartdigitalmarketing.com/wp-content/plugins/super-forms/uploads/php/files/930ec81f90fbbc06028a244eef55481e/69391020689.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5dfe5d066d---fawazudofapazujeribunip.pdfIn PDF document text
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c0e6f486e6---12810077553.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a8f9488738---22425459722.pdfIn PDF document text
    • http://qhs1978.com/clients/d/dd/dd8db5a278a7ad55a2ada34b8e38ebcc/File/pumixufavesuzavupuw.pdfIn PDF document text
    • https://sidexsideaudio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084dcfa9c155---79517408815.pdfIn PDF document text
    • https://x-software.cz/data/file/35071838599.pdfIn PDF document text
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/5ab9b9d414816e608eeda236694e4dd4/vuweladag.pdfIn PDF document text
    • https://www.travelticket.com.au/wp-content/plugins/super-forms/uploads/php/files/pv9279plqvv4tb42vulou6t7tl/tijirupiruj.pdfIn PDF document text
    • http://conelser.hu/fck_uploads/file/75670161537.pdfIn PDF document text
    • https://study4student.com/cache/fck_files/file/damimef.pdfIn PDF document text
    • http://diodelumi.com/ckfinder/userfiles/files/milon.pdfIn PDF document text
    • http://psychologkmalinowska.pl/ckfinder/userfiles/files/75329297820.pdfIn PDF document text
    • https://lawyerupsmart.com/tempimg/file/19061613339.pdfIn PDF document text
    • http://canevinclassof70.com/clients/6/6b/6b8b8ee0d314e59372afbcb75100d768/File/rorekaxiwarar.pdfIn PDF document text
    • http://raunlarose.us/wp-content/plugins/formcraft/file-upload/server/content/files/160a00db87f5fa---mekuronojim.pdfIn PDF document text
    • http://skipjackpoke.com/ckfinder/userfiles/files/9546940607.pdfIn PDF document text
    • http://charivne.info/images/file/gopereralogizaderuwuviko.pdfIn PDF document text
    • https://erinmillssmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/njd1mr0s2fs3a4mpar78p3gfc1/xijodasat.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/jc0sr2q0o8qqu6chtfeg62tmsj/fufizojelimesas.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_off0000ea76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA76 10852 bytes
SHA-256: 82f403869fe5cec8a75c4d1ec6a8422c22f051a327e0261daddd2a409160d0b9
font_01_sfnt_off0001038c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1038C 16892 bytes
SHA-256: 72557f15a893e28ebf0a26bea1f2a215ce3ff025e7085a196e861a591144efb4
font_02_sfnt_off00012f95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F95 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1