Malicious PDF — malware analysis report

Static analysis result for SHA-256 b98f932cb1529f33…

MALICIOUS

PDF

69.6 KB Created: 2021-09-25 01:17:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: acb1b123e85924f7fbfd69970712493f SHA-1: 0ee814b2d21c0f236c6126487ab0f1ca82998aa7 SHA-256: b98f932cb1529f337135ea933f8dc5ab93ff0fc5a03265183451887783443b39
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to external PDF files hosted on various domains. Heuristics indicate these are part of a link farm, with some links pointing to compromised CMS upload storage. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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.oalysa.cz/ckfinder/userfiles/files/94481306812.pdf In PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/1613febbc0f25a---19486879827.pdfIn PDF document text
    • https://www.autopsrus.com/ckfinder/userfiles/files/vukiwafepiwikoxalarajudo.pdfIn PDF document text
    • http://sportsbettingconsultants.net/cote_dor_import/admin/ckfinder/userfiles/files/68661766082.pdfIn PDF document text
    • https://gemwares.com/userfiles/file/texugedalupanavadonepad.pdfIn PDF document text
    • https://alhasooncorp.com/Files/files/77587960943.pdfIn PDF document text
    • https://girisimhaber.com/uploads/file/12760457824.pdfIn PDF document text
    • http://bezagsecurity.cz/userfiles/73077908641.pdfIn PDF document text
    • https://gallerylingard.com/uploads/file/nazakikike.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/9df07a8cb4ce791be0e3d6a3e929d36e/75311600946.pdfIn PDF document text
    • http://jiendurancecoaching.com/ckfinder/userfiles/files/56973488173.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614debfa5bfb9---gubiwevevugabute.pdfIn PDF document text
    • http://karate-talence.com/newsite/userfiles/files/32941259387.pdfIn PDF document text
    • http://nena-artspace.com/ckfinder/userfiles/files/fesanu.pdfIn PDF document text
    • http://l-max.ru/userfiles/file/maboloxolegowuvu.pdfIn PDF document text
    • http://dgelc.com/userfiles/file/20210924085218.pdfIn PDF document text
    • https://xyoaa.org/sites/default/files/files/vokelejogi.pdfIn PDF document text
    • https://turkihale.com/userfiles/file/In PDF document text
    • http://xn--80aafkatcapceshpicpg3h.xn--p1ai/pict/file/33567751813.pdfIn PDF document text
    • http://airzo.net/userData/board/file/70283286547.pdfIn PDF document text
    • http://internet-trade.cz/UserFiles/file/40556386488.pdfIn PDF document text
    • http://baohanhranghm.com/upload/img/files/lusoropelujalupiva.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=tiger+woods+iron+specsPDF 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_off0000adf8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xADF8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c60a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC60A 17240 bytes
SHA-256: 94dbfbc9ff1e8d5cab05d631b57f5440b2bf48181663e16363f7b5779aa0527d
font_02_sfnt_off0000f1c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1C2 10432 bytes
SHA-256: 20285222e8814b765c5302d87ca2357dd54a0793f4092a3c94bbaa45c4735f4b