Malicious PDF — malware analysis report

Static analysis result for SHA-256 756387ced8dbab0e…

MALICIOUS

PDF

75.0 KB Created: 2021-09-05 05:44:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: bc21d229c7eeb0d6292fb95e8368d6d5 SHA-1: 505ef7798295bf6fc46b3c3b3aeb8a50fc682508 SHA-256: 756387ced8dbab0e370374708e77ba3d610d907c52bb37e1aa8b92b08551427d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links to external websites, many hosted on compromised CMS platforms, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics indicate an attempt to exploit users through deceptive links, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/bubkeian076ln3usmkrper9mci/73368027.pdf In PDF document text
    • http://drivingschool-brno.eu/files/66863460039.pdfIn PDF document text
    • https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad102d33560---nikiwogowi.pdfIn PDF document text
    • http://nhs1980alumni.com/clients/878257/File/dasenevolegixitorisu.pdfIn PDF document text
    • https://holzhaus-suedtirol.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607db4b8a9833---83927549772.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b297ac3087---43022436556.pdfIn PDF document text
    • http://conblocmanado.com/pics/file/vufejowubigoxef.pdfIn PDF document text
    • https://iieng.org/editor/ckfinder/userfiles/files/68265222633.pdfIn PDF document text
    • https://smithsgame.com/calisma2/files/uploads/80764457701.pdfIn PDF document text
    • http://mmckno2010.zkosuchdol.info/files/tevuzomapofibije.pdfIn PDF document text
    • https://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/805ccf9c8cc5f879161a1c60d89ca93d/70060818030.pdfIn PDF document text
    • http://ototavandosemesi.com/resimler/file/33210202385.pdfIn PDF document text
    • https://asiantms.com/ckfinder/userfiles/files/mumitomu.pdfIn PDF document text
    • http://kiemdinhcan.com/Images_upload/files/21363219900.pdfIn PDF document text
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/6vfklpaqiogon3ptplcv06naj2/24520427703.pdfIn PDF document text
    • http://metabolit.ru/files/file/89519968480.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/basumebo.pdfIn PDF document text
    • http://sweed-trans.eu/ckfinder/userfiles/files/zoronav.pdfIn PDF document text
    • http://chnli.tw/CKEdit/upload/files/93850763046.pdfIn PDF document text
    • http://noithatnhapkhaugiasi.com/luutru/files/jutojokijomexolivag.pdfIn PDF document text
    • https://alixdemassy.fr/userfiles/file/72506681774.pdfIn PDF document text
    • https://phr4u.com/files/naxulasukosisuxojemoz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=sakalas+personalo+vadyba+pdfPDF 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_off0000c06e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC06E 10788 bytes
SHA-256: 7f78ba0345642285c71a168cdba2f87fccaa7f83880b5769b62508f4a5cdb404
font_01_sfnt_off0000d934.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD934 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f146.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF146 18076 bytes
SHA-256: 8c207db3d0bff708405c26e5162e9b59c4d7d85a67a00aaa1dc5dbbcf3913252