Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c962f871561a7cf…

MALICIOUS

PDF

79.1 KB Created: 2021-09-04 22:36:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 4c1d7ae6daf3f9a15f1a89f9230db810 SHA-1: 2084342c3fc2447a2f622034b4d0145f7169c8e3 SHA-256: 4c962f871561a7cf6a6361f7123a271c3cefb5b692284302252be2102d4051dd
164 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 and contains embedded JavaScript. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 7

  • 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.
  • 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.
  • 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 http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/313260ed0c3e693c99adf0f6a8df1eae/6416171953.pdf In PDF document text
    • http://laduses.nl/image/file/56776682587.pdfIn PDF document text
    • http://cheers-gifts.com/userfiles/78694220134.pdfIn PDF document text
    • http://maekalocal.com/Maeka/UserFiles/File/24710171772.pdfIn PDF document text
    • https://www.hausbootgeiseltalsee.de/wp-content/plugins/super-forms/uploads/php/files/3oumip5k5neatvsi00q8gv77iq/vabajideranibusasesotojaw.pdfIn PDF document text
    • https://doitsolutions.co/wp-content/plugins/super-forms/uploads/php/files/ff79aa1f44640d9aad05985bcf772036/kevunebalevi.pdfIn PDF document text
    • https://lea-inc.com/wp-content/plugins/super-forms/uploads/php/files/a2767c93369fd39de694481980f2ffcb/puximelutasep.pdfIn PDF document text
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/qr35h2sadk15r6pauo328datk7/videwunexefabu.pdfIn PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160cf7e28063c9---vizujogevajasinulopimada.pdfIn PDF document text
    • http://owv-sad.de/userfiles/files/17715356407.pdfIn PDF document text
    • http://leebyunghun.kr/new/upload/board/files/donorexu.pdfIn PDF document text
    • http://library.nesdb.go.th/ic/admin/ckfinder/userfiles/files/xomufikasapese.pdfIn PDF document text
    • http://fruitsad.pl/images/file/70915709774.pdfIn PDF document text
    • http://danies.ru/ckfinder/userfiles/files/takowijetetetadawegekugir.pdfIn PDF document text
    • http://rrbrentacars.com/files/others/kefejuzume.pdfIn PDF document text
    • http://thepnguyentran.vn/media/ftp/file/botijude.pdfIn PDF document text
    • https://astefin.ro/ckfinder/userfiles/files/biwevusipumatas.pdfIn PDF document text
    • http://topoint.cc/userfiles/fckFile/20210817014455.pdfIn PDF document text
    • http://esoftland.com/userfiles/file/30570767621.pdfIn PDF document text
    • http://studiosaletta.it/userfiles/files/modukilixezogixidedi.pdfIn PDF document text
    • http://cn-junsheng.com/upload/file///202194164772512.pdfIn PDF document text
    • http://garageanything.com/js/upload/files/mutobonunuxikugawomifod.pdfIn PDF document text
    • https://bancodevida.com/bancodevida/admin/images/image/file/77174409179.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=punctuating+direct+speech+worksheet+year+3PDF 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_off0000ccc1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCC1 11312 bytes
SHA-256: 75056753565e4351e9e3546fa7fcf0db7e2d2b3df338c0144b7599ec5489de90
font_01_sfnt_off0000e73a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE73A 18236 bytes
SHA-256: 53e4667071df24465bb47f3af7a1f9da5cd7e27007d587d038299c75b4c13f9b
font_02_sfnt_off0001166b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1166B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1