Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb1cf4a505ee6950…

MALICIOUS

PDF

82.0 KB Created: 2021-09-08 07:17:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 6aa5a74f8a629d314ffc85070d611c95 SHA-1: fdef5688ac5c612bd52ffecbd6f1aba6d6139d72 SHA-256: cb1cf4a505ee695004fc2619a97d61d3ceca6f8408725aae3cae1689a63b197e
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to compromised CMS upload directories or disposable domains. The ML classifier and ClamAV heuristic strongly indicate maliciousness, consistent with a phishing or malware distribution scheme. The file's structure suggests it's designed to overwhelm the user with links, potentially leading them to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • 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 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 http://ivelinabozilova.com/userfiles/file/62576998408.pdf In PDF document text
    • http://dirabrealtors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e0277d2cca---51696571450.pdfIn PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160ee306632b70---51028630809.pdfIn PDF document text
    • https://amitadevnani.com/userfiles/file/fatov.pdfIn PDF document text
    • https://blackknowledge.com/wp-content/plugins/super-forms/uploads/php/files/852ce1f7d1113bc6543ae4f116873876/sazonoxoru.pdfIn PDF document text
    • http://unityproductions.com/upload/files/66807826702.pdfIn PDF document text
    • http://jaatkinson.com/userimages/38508803259.pdfIn PDF document text
    • https://www.straightmyteeth.com/wp-content/plugins/super-forms/uploads/php/files/cf54d927c80648858f8dab7fe853ea35/79948345871.pdfIn PDF document text
    • http://doudou.tw/userfiles/files/64005185624.pdfIn PDF document text
    • http://kossuthdigisuli.hu/userfiles/file/mupukolimar.pdfIn PDF document text
    • https://bnbcostaverde.it/userfiles/file/50678496343.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/de4c7a87103f8955a21794541d5ba016/75460362132.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/16106fc68c5c7d---tebuwapisaxodowepuluzab.pdfIn PDF document text
    • http://kargiskola.ge/myadmin/ckeditor/ckfinder/userfiles/files/72635805249.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/1608925a61ed0e---gipoxajixoxa.pdfIn PDF document text
    • http://polymer-optix.de/userfiles/file/napufusosikidawoved.pdfIn PDF document text
    • https://oncallanatomist.org/ckfinder/userfiles/files/poxoxekur.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16103152b61d61---80156690270.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/91367682284.pdfIn PDF document text
    • http://doubles301.jp/files/ckeditor/files/doxafilogop.pdfIn PDF document text
    • https://curryleafharleysvillepa.com/hang/userfiles/files/67913513056.pdfIn PDF document text
    • https://ksuskalology.com/images/file/jevirakajigufaneluwejas.pdfIn PDF document text
    • http://dbexpertise.fr/catalogue_dynamique/file/10958196694.pdfIn PDF document text
    • https://tsafar.ir/basefile/tsafarir/files/sowalebamiwiputuk.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=free+split+and+merge+pdf+files+softwarePDF 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_off0000db74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB74 10904 bytes
SHA-256: b87ea11b8480b2d3c2c55e7dc11e041dbc581add52bd9b19d324cac6de4e19aa
font_01_sfnt_off0000f480.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF480 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010c92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C92 17500 bytes
SHA-256: fc244141a94941cf8dcdd15a46e0708e1876e61f3cfb1b61f497354401c5540e