Malicious PDF — malware analysis report

Static analysis result for SHA-256 731e18efe9324a6a…

MALICIOUS

PDF

82.3 KB Created: 2021-09-09 17:21:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 6615af5b192fdd2501ac50e311921842 SHA-1: 0e32bb3f987e56e1bb5976e032e014091bd80b62 SHA-256: 731e18efe9324a6a75f38ec03b4cab46b0a87ef9aac99dfc45830da5d9d5e0c8
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating it functions as a link farm. Multiple embedded URLs point to potentially malicious domains, suggesting an attempt to redirect users to phishing or malware hosting sites. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic specifically highlights the nature of the document as a link farm on disposable hosting.

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://hopefor.today/wp-content/plugins/super-forms/uploads/php/files/e90ebc83724d66a494ab5ee02edadb58/98820832817.pdf In PDF document text
    • https://www.truck-transport.com/ckfinder/userfiles/files/kexanufobokabagotikagabak.pdfIn PDF document text
    • http://svadbavmoskve.com/content/xuploadimages/file/12275610426.pdfIn PDF document text
    • http://cisseo.net/userfiles/files/22280474905.pdfIn PDF document text
    • http://traktorpulling.de/ablage/userfiles/files/gotujo.pdfIn PDF document text
    • http://dayou.tw/uploadpic/files/202109081658024812.pdfIn PDF document text
    • https://pavillonwohlen.ch/userfiles/files/1974463997.pdfIn PDF document text
    • http://newtrichur.com/userfiles/file/xabozumufodawewoluxe.pdfIn PDF document text
    • http://rococosofa.com/files/files/gulotagetonor.pdfIn PDF document text
    • http://a-kamen.com/userfiles/file/fijiramogewofegerib.pdfIn PDF document text
    • http://goldendazzle.com/upload/quangtri/files/61397981385.pdfIn PDF document text
    • https://dom4m.by/userfiles/files/sumubakorawe.pdfIn PDF document text
    • http://paddockj.com/user_data/editor/ckfinder/core/connector/php/upload/files/39495941217.pdfIn PDF document text
    • https://drhuanghair.com/uploads/files/202109072346199956.pdfIn PDF document text
    • http://sun-green.nl/ckfinder/userfiles/files/zoniwenaje.pdfIn PDF document text
    • http://villa-margherita.biz/userfiles/files/zikunoramiliz.pdfIn PDF document text
    • https://sikanderajam.com/Robinson/ckfinder/userfiles/files/gakepopowakefeli.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/549e4710d98437fd56f727b4af2c7ca3/xisafa.pdfIn PDF document text
    • http://kibunajcc.com/ckfinder/userfiles/files/fejag.pdfIn PDF document text
    • https://kalyna.ua/sites/default/files/userfiles/file/61886840094.pdfIn PDF document text
    • http://thietbimaugiao.vn/Images_upload/files/63958032170.pdfIn PDF document text
    • http://ljsmelt.com/upload/files/memini.pdfIn PDF document text
    • http://zhongjiukeji.com/upload_fck/file/2021-9-9/20210909210736506931.pdfIn PDF document text
    • https://ta-taiwan.com/app/webroot/userfiles/files/kiparajokuda.pdfIn PDF document text
    • http://keralastatetailorsassociation.com/userfiles/file/mukanalobogev.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=bahadur+comics+pdfPDF link annotation
    • http://cluster006.ovh.net/~greeters/namur/ckfinder/userfiles/files/15082416342.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_off0000dcc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCC7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f4d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4D9 17696 bytes
SHA-256: 8766111ad184aa5433b857edca5b3d087c2805c0119542f1d733333d09054e62
font_02_sfnt_off00012316.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12316 10656 bytes
SHA-256: c1b655f9cc0da246030fcc14a8d28ca2b8562d9c580a743e3508c1a1d1d115bc