Malicious PDF — malware analysis report

Static analysis result for SHA-256 be42b7782cf10b9c…

MALICIOUS

PDF

86.9 KB Created: 2021-09-17 18:07:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: aa96e5bde41a55b98907675ee2e01d73 SHA-1: 2c2c80401ae378dbeefb3c1c21d938ae18153749 SHA-256: be42b7782cf10b9c44f51c607ad04951f810f3c0f77458b74f3fb4d917cf9036
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a link farm pointing to numerous external URLs, several of which are hosted on compromised WordPress sites or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body is unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 https://www.domaine-boussard-chablis.fr/ckfinder/userfiles/files/37165258936.pdf In PDF document text
    • https://doctmcooper.com/userfiles/files/vegewuraraka.pdfIn PDF document text
    • http://finsura-lifedirect.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613b91695f50f---60575583051.pdfIn PDF document text
    • http://xn--90afqerdlt1f.xn--p1ai/admin/ckfinder/userfiles/files/filiz.pdfIn PDF document text
    • https://tybistanbul.org/resimler/files/70408002151.pdfIn PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/308b5b0f8fd80e16db8e9ec8580463a9/zafelewapowotuxepi.pdfIn PDF document text
    • https://100tmt.com/uploadimage/files/20210902023411.pdfIn PDF document text
    • http://iscelenie.info/files/file/dexinaxezavudaxalenunifu.pdfIn PDF document text
    • https://egokituz.eus/files/galeria/files/71786708726.pdfIn PDF document text
    • http://jubileejec.com/userfiles/files/72234182206.pdfIn PDF document text
    • https://frigosztufi.ro/ckfinder/userfiles/files/4334059845.pdfIn PDF document text
    • http://daydreamspin.com/userfiles/file/bumudaxoparazilawepas.pdfIn PDF document text
    • http://fsf-vastroad.com/userfiles/file/69903600220.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133540b57ce9---9470115329.pdfIn PDF document text
    • http://uitvaartverzorgingsindex.nl/images/uploads/sijiliroxifosov.pdfIn PDF document text
    • https://shen-su.eu/gfx/userfiles/files/17257046322.pdfIn PDF document text
    • http://dayou.tw/uploadpic/files/202109120008102424.pdfIn PDF document text
    • http://tootingtaxi.com/survey/userfiles/files/41386499170.pdfIn PDF document text
    • http://dialog-seversk.ru/jsplugins/ckfinder/userfiles/files/lutolepisujakunaxi.pdfIn PDF document text
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/9f09e0adfdbbc8a573f0ec8cb7b188c7/10132934044.pdfIn PDF document text
    • http://maraulsan.com/ckfinder/userfiles/files/89604328443.pdfIn PDF document text
    • http://brukbet.com/user_images/file/kenurenebowupenap.pdfIn PDF document text
    • http://unternehmensberatung-hegenbarth.de/userfiles/file/barimelomejifak.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=7+iron+loft+degreePDF 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_off0000ef2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF2D 10152 bytes
SHA-256: 6065b1267f1332bd5018f6b7d915baee440da89b99e8e5d670a621f147acdfb7
font_01_sfnt_off000105b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105B9 18476 bytes
SHA-256: 6e60df4c79eae4bea5e75288802bf01cc0a8332ae7f034fd6b782153198f672a
font_02_sfnt_off000135e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135E3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1