Malicious PDF — malware analysis report

Static analysis result for SHA-256 2527323ff52bac4a…

MALICIOUS

PDF

81.5 KB Created: 2021-09-10 02:07:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 4cf89b332e16bd91e2bf004bcf0829fb SHA-1: 938ba4299c705b6fcfcd6aef935f578e2ac5ecd5 SHA-256: 2527323ff52bac4a65ef13ecbcf682d500eb9bb0c62f7e8f857a402a479dff1a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ClamAV and an ML classifier as malicious, with heuristics indicating it functions as a link farm. The document contains numerous embedded URLs pointing to other PDF files, suggesting a tactic to manipulate search engine results or distribute additional malicious content. The presence of many distinct hosts and disposable links further supports this. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://v-lukomorie.com/uploader/files/8556619243.pdf In PDF document text
    • http://moristas.com/userfiles/files/kolexidagumenebenunanided.pdfIn PDF document text
    • https://www.adom.biz.pl/ckfinder/userfiles/files/83564084203.pdfIn PDF document text
    • http://g-shocktou.com/user_file/file/8856247901.pdfIn PDF document text
    • http://ksklinika.ru/ckfinder/userfiles/files/18550799896.pdfIn PDF document text
    • http://sxsasa.org/images_fck/file/1630594641.pdfIn PDF document text
    • https://printsolutions.ro/uploads/wysiwyg/files/wafag.pdfIn PDF document text
    • http://fanghsin.com/uploads/files/202109100601241767.pdfIn PDF document text
    • http://pileki.com/imgup/file/keweloxemibefez.pdfIn PDF document text
    • http://sspvjd.com/FileData/ckfinder/files/20210902_D3584B2CC5534241.pdfIn PDF document text
    • http://www.theflightfest.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613076a2dbfb8---78519575472.pdfIn PDF document text
    • http://codienlanhtrangia.com/Images_upload/files/gafilalubajuforanet.pdfIn PDF document text
    • http://posicert.com/upload_fck/file/2021-9-3/20210903064742355329.pdfIn PDF document text
    • https://regaluxiluminacion.com/uploads/assets/file/39940988090.pdfIn PDF document text
    • http://a2hgghk.handylover.com/upload/files/64905968230.pdfIn PDF document text
    • http://schokoladenfontaene.de/idata/57182351089.pdfIn PDF document text
    • http://xn--80aa5alfu.kz/file/redexumimozet.pdfIn PDF document text
    • http://hzjksj.com/images/upload/File/72044925482.pdfIn PDF document text
    • https://freshchannels.com/home/sites/freshchannels/public_html/ckfinder/userfiles/files/jakevoniluxigarakafiben.pdfIn PDF document text
    • http://pk.mo/userfiles/file/62179741381.pdfIn PDF document text
    • http://photou.cc/ckfinder/userfiles/files/gazadowu.pdfIn PDF document text
    • https://heritran.vn/uploads/news_file/39702196158.pdfIn PDF document text
    • http://cs-golfclub.com/ckupload/files/27551245646.pdfIn PDF document text
    • https://suemsas.com/wp-content/plugins/super-forms/uploads/php/files/p14fgobp69u0s3adok226n05v0/19352579937.pdfIn PDF document text
    • http://resurrection-life.net/userfiles/files/kuwesolesaden.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=how+to+screenshot+on+moto+g5PDF 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_off0000d863.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD863 10588 bytes
SHA-256: d7f0bdc119f1c3eb7ffb1d73ae7cfc4c266d391e02fcf5ee27a7c13a0ba0bf4a
font_01_sfnt_off0000f070.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF070 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010882.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10882 18748 bytes
SHA-256: a617ab4a46fe10efaba3fb273f260ed00ff771f478cca43a57498a2953cb86a4