Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b4c42a4a0dbe7eb…

MALICIOUS

PDF

78.6 KB Created: 2021-09-11 23:32:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: eac09eecf3c3717c5b11f7d1e52fba6b SHA-1: 7cf2a532bed22aac534c52863b763bbc72e45b04 SHA-256: 6b4c42a4a0dbe7eb66c740e2fa5bd5b05c19d8037f3d74007e5804e622d07409
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests the document is designed to host numerous links on disposable domains, a common tactic for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://www.psstrecno.sk/wp-content/plugins/formcraft/file-upload/server/content/files/16134f11e69d72---doroj.pdf In PDF document text
    • http://nacyc.jp/Upload/file/wefavopewajonarakak.pdfIn PDF document text
    • http://as-eng.biz/userfiles/file/zadosiximag.pdfIn PDF document text
    • http://urparitet.ru/admin/ckfinder/userfiles/files/6125879261.pdfIn PDF document text
    • http://ajarnveerapong.com/UserFiles/file/2688674492.pdfIn PDF document text
    • https://studiecarriere.it/uploads/file/94290010488.pdfIn PDF document text
    • http://zabradli-znerezu.cz/userfiles/file/zuremume.pdfIn PDF document text
    • http://akademia-jedenastka.pl/zdjecia/fck/file/dorigatixa.pdfIn PDF document text
    • https://pensiuneavalentina.ro/app/webroot/file/93588645601.pdfIn PDF document text
    • https://dewalt-naradi.cz/media/upload/editor/file/35912978247.pdfIn PDF document text
    • http://2sisaccount.com/userfiles/files/40326552624.pdfIn PDF document text
    • http://fuguchair.com/upfolder/e/files/20210901092316.pdfIn PDF document text
    • https://ltes2.tw-goods.com/UserFiles/files/30473079034.pdfIn PDF document text
    • https://www.rockandroll.blog.br/wp-content/plugins/super-forms/uploads/php/files/6lumullkb2mc7t913k96etk5l9/fizemipadopopasik.pdfIn PDF document text
    • http://rehahomecare.com/upload/editor/files/suvozefuwo.pdfIn PDF document text
    • https://spa-salon.ru/ckfinder/userfiles/files/6736518320.pdfIn PDF document text
    • https://newegys.egyseg.eu/ckfinder/userfiles/files/guxipofuzuvotabogu.pdfIn PDF document text
    • http://purepoem.com/resource/docContentImg/file/2021-09-09/9eaa91925bd81513b963abcc7ead99a1.pdfIn PDF document text
    • http://kahounova.cz/userfiles/file/58289435506.pdfIn PDF document text
    • http://klaaswester.nl/img/file/mojixel.pdfIn PDF document text
    • https://cleaner.pl/userfiles/file/28030047746.pdfIn PDF document text
    • http://www.nbc.com.vn/ckfinder/userfiles/files/52721557753.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=online+bangladeshi+newspaper+and+magazinePDF 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_off0000ceba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEBA 10932 bytes
SHA-256: 66632e2d647301406c8d28de3db5721708f9e3c1a7b820f19b3b071650225570
font_01_sfnt_off0000e78a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE78A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ff9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF9C 17324 bytes
SHA-256: 9d4d54860d210921f94e5b484a26f5e56c07fe91d18980ec9192a4aed29f36e9