Malicious PDF — malware analysis report

Static analysis result for SHA-256 3171295fae468f85…

MALICIOUS

PDF

71.5 KB Created: 2021-09-20 11:08:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8465bbdc24104e334c652d216a76da4a SHA-1: 961370a07727a2e709f1a4f58f69c3cb9e2c3951 SHA-256: 3171295fae468f854478f6d18c2253d8f1ff6d50624e849d65dd047f060b36f8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains numerous external links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users. The presence of embedded URLs and the nature of the heuristics indicate a phishing or malware distribution attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://feuerwehr-mittenwalde.de/mediathek/files/tuvodavulurugozu.pdf
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161477a41b7a91---sitapogidisavoloj.pdf
    • https://fond.ru/userfiles/file/tewuvezupinokif.pdf
    • http://metisentry.net/ckfinder/userfiles/files/loletesenigotidajigetane.pdf
    • http://jaluzipro.ru/public/userfiles/file/vuvaburuwife.pdf
    • https://bcbc3399.com/upload/files/16581747394.pdf
    • https://calienglish.com/ckfinder/images_store/files/19465547905.pdf
    • http://xn--80aafmoni2biho.xn--p1ai/admin/ckfinder/userfiles/files/durujiviwo.pdf
    • http://evolution-dev.com/file_media/file_image/file/24621225847.pdf
    • https://vallejardin.com/wp-content/plugins/super-forms/uploads/php/files/c3e166c5f9c2a7d2861511e17e1a23ed/nimoxek.pdf
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/hckqjhoskepcu5an2tpvjeq1qd/gekujudutixixetubu.pdf
    • http://aptekadc.pl/userfiles/userfile/72506543632.pdf
    • https://www.pal-kont.hu/wp-content/plugins/super-forms/uploads/php/files/1ad263fed2ab14f52648615d12af07b8/31445012476.pdf
    • https://pmrmhss.com/userfiles/file/4661613625.pdf
    • https://www.southdownscellars.co.uk/ckfinder/userfiles/files/gaxigatefagifale.pdf
    • http://jenistudio.com/upload/FCK/file/63409281361.pdf
    • http://deaprogettazioni.it/userfiles/files/45864870559.pdf
    • http://energcomb.net/cms_enercomb/sgi_userfiles/userfiles/files/71421950729.pdf
    • http://geriatriccarenewjersey.com/userfiles/files/zatebolokadoganojagorina.pdf
    • http://cappellastudio.it/userfiles/files/mokeludodubipofezatixaw.pdf
    • http://mindatpeace.us/uploads/files/8503634326.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=dbt+for+depression+pdf
    • 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_off0000b800.bin
0f72bdd1893f309b2a1d79ec9284ae32f201855562dbab29294c7b2b009d1c9a
pdf-font-stream PDF embedded font (sfnt) at offset 0xB800 16224 bytes
font_01_sfnt_off0000e12c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE12C 16792 bytes
font_02_sfnt_off0000f943.bin
0942aa7392a6738724869de8abc57adb7b514100c2923be14dea3e225f477301
pdf-font-stream PDF embedded font (sfnt) at offset 0xF943 10424 bytes