Malicious PDF — malware analysis report

Static analysis result for SHA-256 1625cf682dcb839e…

MALICIOUS

PDF

75.5 KB Created: 2021-09-17 04:46:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7e102d6444c790dbabbdad26da9a19ed SHA-1: 4eabf3af6c9e5b4d48ecafabd04ab3255bda8178 SHA-256: 1625cf682dcb839e249a8518eaf65fe524c7e17cfe65b6b7d1b42737ffcccd06
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains, indicating a link farm designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristic firings suggest an attempt to exploit users through malicious links, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • 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://huangs.tw/uploads/files/202109081955057595.pdf
    • http://crocepadrekolbe.it/userfiles/files/jesugodedusagil.pdf
    • http://charontrade.hu/data/file/vuladufufezurezoligonuka.pdf
    • https://andymullinscommercial.com/home/andy/public_html/ckfinder/userfiles/files/ruweketos.pdf
    • http://www.sunarnuricomuisvealisverismerkezi.com/wp-content/plugins/super-forms/uploads/php/files/8td4tubd7olpvtn08d2cphonq5/rawibijawuzubelumig.pdf
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16133962612892---jaronikiradebumebamajetav.pdf
    • http://yanartextil.com/firma/files/zojadefalaluzenuvelasen.pdf
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cd771e7f45---62402919928.pdf
    • http://emachn.com/data/attachment/file/duloregafunenegija.pdf
    • http://tinhdaurosa.com/Images_upload/files/vajizebosukakanixigim.pdf
    • http://0985028898.kad.tw/kads/ckfinder/userfiles/files/wokowiweloxozerir.pdf
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/1613c3d1c681fd---muxenofadedenipekif.pdf
    • http://copingconversations.com/userfiles/file/bubijupiruxi.pdf
    • https://balarampurblock.in/ckfinder/userfiles/files/redijipo.pdf
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/ba2229233308ca086db9ded8cdcff2d2/37987105108.pdf
    • https://adtw1.elfjane.com/ckfinder/userfiles/files/77730118439.pdf
    • http://ozt.zielonetarasy-cieplice.pl/uploads/userfiles/files/11815460421.pdf
    • https://corcreation.twbiz.me/data/fckeditor/files/20210906_231127.pdf
    • https://northcoteplaza.com/userfiles/file/84071899477.pdf
    • http://romangruszecki.com/uploaded/file/15869790793.pdf
    • https://interference.ajoda.eu/userfiles/files/11309771736.pdf
    • https://minipowerpack.net/upload/files/9323244841.pdf
    • https://postelezmasivu-zlin.cz/ckfinder/userfiles/files/vitusuradu.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=chaos+walking+movie+online
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c0b8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC0B8 16792 bytes
font_01_sfnt_off0000d8cf.bin
f1460745fb5cc01d019e95ada4c7b4e3fe2d1d400b929abddf19ed4c6111bf75
pdf-font-stream PDF embedded font (sfnt) at offset 0xD8CF 10632 bytes
font_02_sfnt_off0000f108.bin
985eba0c34484a0869fb01b365f264d90eb83098eedec28eb5bd65df466925b0
pdf-font-stream PDF embedded font (sfnt) at offset 0xF108 18492 bytes