Malicious PDF — malware analysis report

Static analysis result for SHA-256 88874ff712e43a5c…

MALICIOUS

PDF

72.8 KB Created: 2021-09-03 15:37:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: f34a0b12bc2785e6f7d827f6e33c28d2 SHA-1: a53cbeb61ca97e95570e06743a3f01bda0f229c7 SHA-256: 88874ff712e43a5cd293c33a7a0d88ec0835d79e62ac0b131f307d2fc9abfd3f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8008b87eef---sefixamirujoda.pdf In PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075ec3ba5fb5---rilesetokidu.pdfIn PDF document text
    • https://aakritidigitals.com/userfiles/files/xiramevisokunujif.pdfIn PDF document text
    • http://gyndoktors.de/ckfinder/userfiles/files/66097949467.pdfIn PDF document text
    • http://viviapalermo.com/userfiles/files/lijoxuz.pdfIn PDF document text
    • https://hinaweb.com/upload/file/49925940513.pdfIn PDF document text
    • http://sosnovgeo.ru/userfiles/file/bopaf.pdfIn PDF document text
    • https://mehfermobilsaglik.com/userfiles/file/diwuwesox.pdfIn PDF document text
    • http://micronforgacsolo.hu/UserFiles/file/pepamote.pdfIn PDF document text
    • http://eventclub.pl/userfiles/file/97211823256.pdfIn PDF document text
    • https://perfecthospitals.org/ckfinder/userfiles/files/96170169526.pdfIn PDF document text
    • http://clarksville.net/wysiwygfiles/file/92350966425.pdfIn PDF document text
    • http://clarasonic.com/upload/file/nibobijeloloxowujo.pdfIn PDF document text
    • http://shreyaghoshal.com/konadnew/userfiles/file/mibisikedexogevijo.pdfIn PDF document text
    • http://lovesenergy.com/file/vexem.pdfIn PDF document text
    • http://fundacionecla.org/resources/original/file/60613241410.pdfIn PDF document text
    • http://www.findvoters.com/userfiles/file/9837366814.pdfIn PDF document text
    • https://pellevah.com/upload/files/mivamesibosav.pdfIn PDF document text
    • http://bjaimama.com/data/upload/2021/05/file/202105150301117455.pdfIn PDF document text
    • http://qianshunqs.com/admin/upload/josepawazedazibamuduzumo.pdfIn PDF document text
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/0e3d2a1aec25a470190e5739aac7b5f8/13207043453.pdfIn PDF document text
    • http://aquatrustfina.com/userfiles/file/96427152030.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606ec8e266119---jebuxorulesareg.pdfIn PDF document text
    • https://masukpt2.com/contents//files/21727781551.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=types+of+leadership+approaches+pdfPDF link annotation
    • 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_off0000bbf9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBF9 10592 bytes
SHA-256: b3b0e39acd0ffa2899e8c0554f31689908a5b80228a90b5d6589b73e423bea23
font_01_sfnt_off0000d44b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD44B 16184 bytes
SHA-256: 2b2f1a674eef5abd27155a06dba7ded81ff85761938091a893f78a8f993e1684
font_02_sfnt_off0000fd3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD3A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1