Malicious PDF — malware analysis report

Static analysis result for SHA-256 82334ed428b46499…

MALICIOUS

PDF

79.2 KB Created: 2021-10-09 17:56:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: dc8e341f5d42637fd66f5c13eb1694dd SHA-1: dc0d12b4f2da841be14c55f4611d80e8ce1c5583 SHA-256: 82334ed428b46499db33ca489c6bb03225e1a502329d401ade7d78f13efe1a2f
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many of which point to websites hosted on compromised Content Management Systems (CMS) or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware through these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL analysis and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://delcinfo.ru/img/files/files/fuvidisemurob.pdf In PDF document text
    • https://livres-arts.com/ckfinder/userfiles/files/gikexupazoviw.pdfIn PDF document text
    • http://www.pointcookelectrician.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16150bbb5c8bed---perovokegekuleditexeruv.pdfIn PDF document text
    • http://www.espaciocultivarte.com/ckfinder/userfiles/files/95920475625.pdfIn PDF document text
    • http://nhasachthunam.com/upload/files/13761639986.pdfIn PDF document text
    • http://chizclean.ru/files/fck/file/5023196509.pdfIn PDF document text
    • http://www.tobywells.org/media/fckdir/file/muteziw.pdfIn PDF document text
    • https://sibois.eu/userfiles/file/13222911739.pdfIn PDF document text
    • https://doanhnghiepvietnam.org/img_duhoc/files/guxedaruzezuz.pdfIn PDF document text
    • http://scbczy.cn/up_files/file/20210915_085336.pdfIn PDF document text
    • https://doanandieuduong295doson.vn/namthuan/images/news/files/39586153660.pdfIn PDF document text
    • http://bluekeydigital.com/images/pic/file/fuzatofimebufenoli.pdfIn PDF document text
    • http://bibliotekaszamocin.pl/img/upload/files/vurav.pdfIn PDF document text
    • https://ibeguiristain.com/userfiles/files/jiferaparajakega.pdfIn PDF document text
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/6a031025cd0b442d2be756276642fc6b/riwulemoleda.pdfIn PDF document text
    • http://melvin.cz/data/tewojukofaxuboj.pdfIn PDF document text
    • http://dienlanhtruongson.com/upload/files/99592045525.pdfIn PDF document text
    • http://greentreeprep.com/cote_dor_import/admin/ckfinder/userfiles/files/84268177834.pdfIn PDF document text
    • http://norilskgu.ru/userfiles/file/73574684242.pdfIn PDF document text
    • http://refah4ter.info/basefile/hotelrefah4terir/files/86741008779.pdfIn PDF document text
    • http://bet-balance.com/userfiles/file/lefisupisirazuxavixagul.pdfIn PDF document text
    • http://thailand.metten.dk/ckfinder/userfiles/files/7066194687.pdfIn PDF document text
    • http://proallprint.com/userfiles/files/lewimiwawegipabebev.pdfIn PDF document text
    • https://charming-dc.com/uploads/files/202109290246115668.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613106fbd8b09---86893528426.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=looking+glass+animal+rescuePDF 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_off0000d059.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD059 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e86b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE86B 17888 bytes
SHA-256: 219af31e12f00ccd6a4ae06a5e3145ed9ea725714a66aa5a3328e4aabbe72988
font_02_sfnt_off000116b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116B6 10624 bytes
SHA-256: 4320990834d7569187914fe4570b12ce9035de4e28ecb04162df7506013d2afb