Malicious PDF — malware analysis report

Static analysis result for SHA-256 372cb747f02fd1a3…

MALICIOUS

PDF

82.2 KB Created: 2021-10-20 13:58:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 8bfb8f43dfe6483d7c6ab0ae2c2e246d SHA-1: 03df4c67ec87001eb2a141f5312581bd913a32d6 SHA-256: 372cb747f02fd1a3bccf057ed1a2e83c5a3999eee97b8b10b73989bceb453b77
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external URIs, many of which point to disposable domains and are structured as link farms, a common tactic for phishing or distributing further malware. The presence of embedded URLs and the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggest a malicious intent to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9917

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 https://yauspeshen.com/ckfinder/userfiles/files/83845374723.pdf In PDF document text
    • https://dd-inside.de/userfile/file/In PDF document text
    • http://hotelniagararimini.eu/userfiles/files/39585331539.pdfIn PDF document text
    • https://faresaldabbous.com/uploads/files/pepuvepagu.pdfIn PDF document text
    • http://gzcaifeilai.com/ckfinder/userfiles/files/202109271745229220.pdfIn PDF document text
    • https://hkbca.org/UploadFiles/file/20210905205710131.pdfIn PDF document text
    • https://pomacanthe-art.fr/imagebeforeafter/files/dasevalavizik.pdfIn PDF document text
    • http://olgapolyakova.de/files/files/24486695584.pdfIn PDF document text
    • http://fiumaradelsossio.it/userfiles/files/vakuv.pdfIn PDF document text
    • https://efficimm.fr/userfiles/files/31272222331.pdfIn PDF document text
    • http://2446665a.ru/ckfinder/userfiles/files/firofevezomezibupewazi.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/161585075a2170---libuwabujor.pdfIn PDF document text
    • https://funbugs.ie/userfiles/file/78861810472.pdfIn PDF document text
    • https://berbagiangka.com/contents/files/xuribedibejurikorasibetot.pdfIn PDF document text
    • https://muratay.nl/userfiles/file/dirotizawizexiwa.pdfIn PDF document text
    • http://margheritango.it/userfiles/file/tevojavu.pdfIn PDF document text
    • http://rebizplus.com/userfiles/file/tubaxotajor.pdfIn PDF document text
    • https://laatjehuisweerstralen.nl/upload/file/6293445689.pdfIn PDF document text
    • http://sbsedupatti.com/sbsedupatti/userfiles/file/dokodojexuzib.pdfIn PDF document text
    • http://maslatalaia.com/userfiles/file/98652162569.pdfIn PDF document text
    • http://expertworker.paraleumarian.ro/app/webroot/files/userfiles/files/95670583697.pdfIn PDF document text
    • https://svarovanijelinek.cz/ckfinder/userfiles/files/dokitenotojivirunizunave.pdfIn PDF document text
    • https://psiakocky-potisk.cz/webpagebuilder/ckfinder/userfiles/files/49306767985.pdfIn PDF document text
    • https://suativisamsungtaihanoi.net/upload/files/98814575577.pdfIn PDF document text
    • http://nbc.com.vn/ckfinder/userfiles/files/74035325729.pdfIn PDF document text
    • https://cqhuaan.myhost360.cn/upload/files/09-30-20-08-43-16.pdfIn PDF document text
    • http://feedproxy.google.com/~r/MbOu/~3/4dZi1sgP-vI/uplcv?utm_term=bts+you+love+you+love+you+love+i+miss+thatPDF 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_off0000d8dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8DD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f0ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0EF 18808 bytes
SHA-256: ac41289eda350ad66c39e3a260cbe5155a278df763acc8c9df397180c97e6931
font_02_sfnt_off0001209b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1209B 10500 bytes
SHA-256: 62694b8ad3e81c9ef20b090f865e2784bed264148244d96ae56a91f72ce82957