Malicious PDF — malware analysis report

Static analysis result for SHA-256 37667e687c0cde21…

MALICIOUS

PDF

74.7 KB Created: 2021-06-19 05:52:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-04
MD5: 1ccee57280327ca62eca5d749836ce79 SHA-1: cfe8f7ea4ac0dcfd377fa5b7a079e802bcf15501 SHA-256: 37667e687c0cde21dd6257006640d3d914ed8a600c3d35ef5d8bf361d9f6ad95
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

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 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/l53r8n5g9ptvg01g9k5gjs2p94/43910702301.pdf In PDF document text
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc4b00b0635---25675906867.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/160900dc54dd14---65606117487.pdfIn PDF document text
    • http://ketnoikienthuc.com/upload/files/29781749443.pdfIn PDF document text
    • https://aduanaldelvalle.com/userfiles/file/nedenewe.pdfIn PDF document text
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/b41015cf91ef6eca29b48e06495c8163/wubanexogagabedamiximel.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/4b991b9ceb594549868ee950894b9433/feguzimevuvalu.pdfIn PDF document text
    • http://easyreturn.store/userfiles/file/zofav.pdfIn PDF document text
    • http://linkingpeople.info/userfiles/file/naturef.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16070904c8d8a0---70932525059.pdfIn PDF document text
    • http://strahovka66.ru/userfiles/file/bobesowe.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/1608c5cac2826d---80302134551.pdfIn PDF document text
    • http://brighterhealthcare.co.uk/wp-content/plugins/super-forms/uploads/php/files/rcun8iamr8sobdqd7ub9bpk3kb/47908256321.pdfIn PDF document text
    • http://orosweb.hu/ckfinder/userfiles/files/minexaloxam.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=hanuman+chalisa+by+ms+subbulakshmi+with+tamil+lyricsPDF 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://scripts.sil.org/OFLIn 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_off0000c316.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC316 5052 bytes
SHA-256: a8fd8fda6d05d4c861f3704700bc9774b992ad3704d48c13fa04dec8c64a0673
font_01_sfnt_off0000d417.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD417 10944 bytes
SHA-256: b8f125e4e3fa0e60021188d6a187af78c0c7e26809d5dbd94b4e88a34df70978
font_02_sfnt_off0000f9ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9AD 16228 bytes
SHA-256: d5d85e3aaaa5992967d3bcc314d74791cb71fca714f8331f5cf69889fcc7a56c
font_03_sfnt_off00010f17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F17 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378