Malicious PDF — malware analysis report

Static analysis result for SHA-256 332a801a2fb26be4…

MALICIOUS

PDF

80.5 KB Created: 2021-10-04 14:34:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: f85790f21d23f20a0d870eb68de7338a SHA-1: cb8ce4035a1b0c6c52896e6a055e52c888f70b8c SHA-256: 332a801a2fb26be4784b00da0e361d787db06743ccaf060b70b8efa395de30b1
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by a machine learning classifier and ClamAV as malicious. It contains numerous embedded URLs pointing to external PDF files, suggesting a link farm or redirection mechanism. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of hosting many links on disposable domains, often used for SEO poisoning or phishing lures. While no scripts were explicitly extracted, the PDF structure and numerous external links strongly suggest an intent to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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://coretry.ru/uplcv?utm_term=caprylyl+glycol+natural PDF link annotation
    • http://gz-theoutfit.com/UploadFiles/FCKeditor/20210927203013.pdfIn PDF document text
    • http://goodtraefarm.com/ckupload/files/vowuba.pdfIn PDF document text
    • https://tahubunting1.com/contents/files/44123198685.pdfIn PDF document text
    • http://yangs-ns.com/ckfinder/userfiles/files/20210923000146.pdfIn PDF document text
    • http://stellamaris.cz/userfiles/vunafiwitimapoliz.pdfIn PDF document text
    • https://perbloland.com/userfiles/file/voxizazafo.pdfIn PDF document text
    • http://www.tlo.ntou.edu.tw/ckfinder/userfiles/files/18530720567.pdfIn PDF document text
    • https://stehovani-ostrava.cz/static_pages_files/file/43728645011.pdfIn PDF document text
    • https://bloomlight.pl/_bloom/file/41837635603.pdfIn PDF document text
    • https://tort-art.ru/userfiles/file/kegikudiwat.pdfIn PDF document text
    • https://economiadecomunion.com/ckfinder/userfiles/files/52233080481.pdfIn PDF document text
    • http://constantemail.com/userfiles/file/1633036464barikiwubimudev.pdfIn PDF document text
    • https://hahapediatric.com/uploads/files/202109030334172244.pdfIn PDF document text
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/1613cb910d2744---podakuku.pdfIn PDF document text
    • https://namdolove.com/FileData/ckfinder/files/20210904_AE114A9711A1B396.pdfIn PDF document text
    • http://togul.org/sites/default/files/file/jopibik.pdfIn PDF document text
    • http://prvugkh.ru/uploads/files/11280727218.pdfIn PDF document text
    • http://fese.in/ienupdimages/images/files/moxapivo.pdfIn PDF document text
    • http://formpart.com/upload/ckfinder/files/jofazunene.pdfIn PDF document text
    • http://top1np.com/ckfinder/userfiles/files/30564901169.pdfIn PDF document text
    • https://maintogelonline.bet/contents/files/29141066083.pdfIn PDF document text
    • https://thefencedocumentary.com/adminfiles/file/folefonademugakifosogugil.pdfIn PDF document text
    • http://boxethai38.com/upload/file/63638493989.pdfIn PDF document text
    • http://sgrappresentanze.eu/userfiles/files/1949992255.pdfIn PDF document text
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139b6513b16d---xakapuwapibusirekum.pdfIn PDF document text
    • http://www.ekoforte.com/upload/file/kusupudelupotitavimuxa.pdfIn PDF document text
    • http://anhuicrew.com/upload_fck/file/2021-9-7/20210907232750177607.pdfIn PDF document text
    • 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_off0000d1f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1F8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ea0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA0F 10404 bytes
SHA-256: 85c6c4eee58943d41b199f7cd9bea04847cbb38156686144a5cc91ccab049876
font_02_sfnt_off000101cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101CD 19660 bytes
SHA-256: 3d8d02f00ec31269d1bab803fe093c278b8d2b20d6d39dffad680973fd821c62