Malicious PDF — malware analysis report

Static analysis result for SHA-256 356675cbe1f8a513…

MALICIOUS

PDF

75.4 KB Created: 2021-09-17 10:07:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 75ce53ec3c22afcb4590f1ef9f5c38fb SHA-1: 6ac45f9edce9ec3769249c7f3bc9dfe8a7a287c8 SHA-256: 356675cbe1f8a5132c5d5e1ca7b23647c9636f9e494264e99c60abbed122035e
132 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and multiple links pointing to external resources, including a raw IP address and compromised WordPress upload directories. The presence of a visual download button and a link farm on disposable hosting suggests a lure to download further malicious content. The ML classifier strongly indicates malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

Heuristics 8

  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://pixomot.ru/uplcv?utm_term=pubg+impressive+message+ringtone PDF link annotation
    • http://flapboxes.custompackageboxes.com/userfiles/files/36832933185.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/161427b19c3828---65797236375.pdfIn PDF document text
    • http://spbi.cz/res/file/42499151007.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1612f07a568120---14607191187.pdfIn PDF document text
    • https://polnische-zaune.de/userfiles/file/bazinamivefadus.pdfIn PDF document text
    • http://tomekorea.com/userData/board/file/12529782810.pdfIn PDF document text
    • http://vmkmsz.hu/userfiles/file/38298757679.pdfIn PDF document text
    • https://protrialse.eu/files/files/notawuwusepinapewozis.pdfIn PDF document text
    • http://lnaixi.com/userfiles/file/20210908182015_673943271.pdfIn PDF document text
    • http://bidwoodmachine.com/d/files/nejag.pdfIn PDF document text
    • http://newgrids.com/userfiles/file/tuzukafemujofin.pdfIn PDF document text
    • http://kahounova.cz/userfiles/file/62533476574.pdfIn PDF document text
    • https://ofcourselc.com/admin/uploadsfile/10094758700.pdfIn PDF document text
    • http://avvocatoandreabruschi.it/userfiles/files/46722401183.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/1613de1618236c---14198198586.pdfIn PDF document text
    • http://nagakuratrading.com/js/upload/files/sumawilekus.pdfIn PDF document text
    • https://osikovo.eu/webroot/img/content/files/kexogilanozupimewej.pdfIn PDF document text
    • https://soportedevida.mx/ckfinder/userfiles/files/26240243413.pdfIn PDF document text
    • http://sriraghavendratemple.com/ckfinder/userfiles/files/11478750553.pdfIn PDF document text
    • https://ctners.com/ckfinder/userfiles/files/kilifofopivatikif.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f43f87dfa7---63747205428.pdfIn PDF document text
    • https://mariapolis.es/ckfinder/userfiles/files/99197656821.pdfIn PDF document text
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/1612ee77b31f6f---82836535750.pdfIn PDF document text
    • http://virus-safe-zone.com/ckupload/files/19560400601.pdfIn PDF document text
    • http://140.121.161.111/ckfinder/userfiles/files/11788429582.pdfPDF link annotation
    • http://mail-ex.net/userfiles/file/38290759718.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_off0000c103.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC103 10856 bytes
SHA-256: 3b59bc5bee816022d57cdef971e02b4616adec5e89f4ab5fd91dbfa0ffb49e7c
font_01_sfnt_off0000d9e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9E4 17672 bytes
SHA-256: 78ff5135ff4172513e45e4dc7e9239f8edb2cad7278c73bd073bd358b08d36dc
font_02_sfnt_off0001080d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1080D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1