Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdbfb2b42802c2a8…

MALICIOUS

PDF

83.4 KB Created: 2021-08-26 06:18:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 0dea76f0e1b4b4d475c55147e5292e26 SHA-1: 6f9485d1d0ed7049cb50a0854723e12775295e3b SHA-256: cdbfb2b42802c2a8546fbbf95d9aa012992cc83613f6d9232391d2d705ef8f7c
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as a link farm, with many URLs pointing to compromised CMS uploads and disposable hosting. The ML classifier and ClamAV also identified it as malicious, specifically a phishing trojan. The document body is unreadable, but the presence of numerous external links suggests an attempt to redirect users to malicious sites for further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

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://dianacb.cz/userfiles/file/55899474970.pdf In PDF document text
    • http://zechnerbau.at/images/content/files/86077717066.pdfIn PDF document text
    • http://sakirnoopo.ru/wp-content/plugins/super-forms/uploads/php/files/225235075022b24b89d05a1ef4d5e726/63898928046.pdfIn PDF document text
    • http://rahwayhigh.com/clients/42761/File/nefukemotiwovovuxe.pdfIn PDF document text
    • http://godswaynehemiahmbc.com/clients/878002/File/70661380061.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a62937e8c6a---69289348720.pdfIn PDF document text
    • https://bringem.de/wp-content/plugins/super-forms/uploads/php/files/1a4457cf75ea11cf7e5aac92d2a0a151/jidamubagididifo.pdfIn PDF document text
    • https://alphacleanwashing.com/wp-content/plugins/super-forms/uploads/php/files/fafd485a9864c7987afce4663adf9c98/66429548663.pdfIn PDF document text
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e9bcb5d558---kedixelezes.pdfIn PDF document text
    • http://c2r-auto.com/uploadfiles/file/2021060909144773499.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078e925d058e---86797361808.pdfIn PDF document text
    • http://honda-vo.com/upload/file/zijoduso.pdfIn PDF document text
    • http://auto-spec.ca/fck/file/xetuwituzuxakez.pdfIn PDF document text
    • https://grandplaza.bg/uploads/assets/file/20643901418.pdfIn PDF document text
    • http://vector-luczak.pl/new/fck_user_files/file/19149013687.pdfIn PDF document text
    • http://haai.org/upload/file/73457600171.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/c1c064222ffa7b1d6b05d88b688b147b/kasil.pdfIn PDF document text
    • http://shyjjc.com/v15/Upload/file/2021724167296737.pdfIn PDF document text
    • http://thebeautyofdesign.nl/ckfinder/userfiles/files/85805452569.pdfIn PDF document text
    • http://verdantnorwich.com/clients/3/30/306756bb587dffcd11ca74610d845a16/File/nutakekopubovogip.pdfIn PDF document text
    • https://celebicatering.com/upload/ckfinder/files/fekurokogewifalosofud.pdfIn PDF document text
    • http://1960whs.com/clients/7/73/73384dfd0d582a2861cf356c55c3c578/File/46905115313.pdfIn PDF document text
    • https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/a6490d3564c3ed4959313045ce979ee0/toxikejetoviwipatovapesok.pdfIn PDF document text
    • http://hutergroup.de/userfiles/file/xarixesulitorowizefaxoriz.pdfIn PDF document text
    • http://longarmquiltacademy.net/fckeditor/userfiles/file/xebofokuxizifokipag.pdfIn PDF document text
    • https://kicksomeglass.com/wp-content/plugins/super-forms/uploads/php/files/4a720b1a7eae6d91b59003c905a940ab/guzenedexefewenaxewine.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=washed+out+face+upPDF 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_off0000e0eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE0EB 10468 bytes
SHA-256: af0fa64b511f9ef9f951eba2c3803549e6a54d38ba0650e5fecb39042c4995b4
font_01_sfnt_off0000f8e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8E3 17632 bytes
SHA-256: 5b638899e6f0ccd26d68f4556195cb50440c17ab08f0d47962db5ee7957e1836
font_02_sfnt_off0001268a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1268A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1