Malicious PDF — malware analysis report

Static analysis result for SHA-256 8f5ffbed74da5c4b…

MALICIOUS

PDF

96.4 KB Created: 2021-09-13 07:26:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 5dacd4bc5e8e8cd2468bd7698ebfe474 SHA-1: ceafb70163098f48555874378201bea8214ad0c9 SHA-256: 8f5ffbed74da5c4b3631163bfd0be914ab0ccfd5a2c76809633add3fa55a9d43
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code within documents. Several heuristics indicate the presence of link farms pointing to compromised websites and potentially disposable hosting, suggesting a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or trojan delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://felicitareonline.ro/ckfinder/userfiles/files/27629647692.pdf In PDF document text
    • https://knurussian.kr/DATA/upload/files/202109101459249516.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/8f34700d186bdaefcd016bdd2e8eac0e/44429314965.pdfIn PDF document text
    • http://dylogistics.com/userData/board/file/54399942185.pdfIn PDF document text
    • https://flour.co.uk/ckfinder/userfiles/files/52280433253.pdfIn PDF document text
    • http://codienlanhminhquang.com/upload/files/buwawinuxabelarowuduxeb.pdfIn PDF document text
    • https://cincia.ro/ckfinder/userfiles/files/donit.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132a1472a2bd---luguluw.pdfIn PDF document text
    • http://szymonadamczyk.pl/uploads/fck/file/61063077640.pdfIn PDF document text
    • https://sreekanakananda.com/ckfinder/userfiles/files/rekebivazuzo.pdfIn PDF document text
    • http://olsztyntransportmedyczny.pl/userfiles/file/12487079980.pdfIn PDF document text
    • http://klaaswester.nl/img/file/kimemivabonineguvutamuru.pdfIn PDF document text
    • http://e-cluny.cz/UserFiles/file/kigapidadasasu.pdfIn PDF document text
    • http://reelproductionshd.com/userfiles/file/43593618624.pdfIn PDF document text
    • http://coaching-scolaire.net/userfiles/file/dipapigipiludinapa.pdfIn PDF document text
    • http://brava-ekb.ru/userfiles/file/lunojirabidifugusitam.pdfIn PDF document text
    • http://ccsup.co.th/uploads/ckfinder/files/zojifevonuraxem.pdfIn PDF document text
    • http://csc025.com/userfiles/file/20210903002514_b950uj.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613812047c7f3---mizumuzorazepagegexato.pdfIn PDF document text
    • https://bdaudit.ro/userfiles/file/funomugoranubamibigig.pdfIn PDF document text
    • http://insei.eu/userfiles/files/lumakimos.pdfIn PDF document text
    • http://jr-bang.com/uploadfiles/20210912213815.pdfIn PDF document text
    • https://www.loscam.com/lib_common/ckeditor/ckfinder/userfiles/files/jabujek.pdfIn PDF document text
    • https://alsharqcc.com/userfiles/files/43031097929.pdfIn PDF document text
    • http://www.sainteuphrasia.com/www/js/ckfinder/userfiles/files/duzuzapowazitatekosiv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=how+to+cast+tablet+screen+to+tvPDF 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_off000116fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116FE 10412 bytes
SHA-256: c0cd75a2d148bcf92128a037d860c6e4024c46c90fab2a0813716ef137ad4f9b
font_01_sfnt_off00012eca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12ECA 17264 bytes
SHA-256: 659ddbef29dea0c6a109ac1accce4949a03e2f3ffeb145361906ea3529c4b6cc
font_02_sfnt_off00015b9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15B9B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1