Malicious PDF — malware analysis report

Static analysis result for SHA-256 c797720c00ef761e…

MALICIOUS

PDF

75.0 KB Created: 2021-09-03 19:37:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 18a8d1872ed5f2527a53fb75032c6b4a SHA-1: 725793744e4588c1b90ef05cf684a64a0abe6f5a SHA-256: c797720c00ef761e7e004bc729ef163068f21d4c11d372b5fe0b8738e26b1405
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many of which point to domains that appear to be compromised or disposable, suggesting a link farm designed to redirect users. The presence of these links and the overall structure indicate an attempt to lure victims to external sites for malicious purposes, likely phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9914

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://we-plus.tw/ckfinder/userfiles/files/vobazasuwewefevubom.pdf In PDF document text
    • http://brickchamber.com/ckfinder/userfiles/files/23030431338.pdfIn PDF document text
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/6f0a940f308f7540247a885c57b7bb26/62776054346.pdfIn PDF document text
    • http://torremaggiore.sitmap.it/files/files/gakokaberowuxobap.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7d6696c8cf---41872756052.pdfIn PDF document text
    • http://baove247.org/upload/files/34382388039.pdfIn PDF document text
    • https://gonguyenkhoi.vn/upload/files/xutuvovejufilopugup.pdfIn PDF document text
    • http://pro-elec.ru/ckfinder/userfiles/files/49715134153.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a8ccdd13360---95334617761.pdfIn PDF document text
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/761bb99a9479b402a6980982cf8ba888/pekagixokebot.pdfIn PDF document text
    • https://europeancustomtailor.com/wp-content/plugins/super-forms/uploads/php/files/426e96783ee3514a983189318b9e303f/80408667882.pdfIn PDF document text
    • http://gucaoyun.com/uploads/file/272228256530.pdfIn PDF document text
    • http://narcisse.sk/editor_uploads/files/97076817476.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16082f16752ab7---50075093814.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160832b61e0992---pavofuvudisefavot.pdfIn PDF document text
    • https://technische-dokumentation-hoffmann.com/upload/files/rexuxabakunadupe.pdfIn PDF document text
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/e94b7fcae51ee4acc6fca4b9701cf8e8/89119840088.pdfIn PDF document text
    • https://signika.pl/Upload/file/36942024723.pdfIn PDF document text
    • https://prosegik.com/wp-content/plugins/super-forms/uploads/php/files/c46cc2b4d434d8d9423604a458cc2045/milobijara.pdfIn PDF document text
    • http://kraljicabih.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afe724cc6c2---84671167692.pdfIn PDF document text
    • https://ocvirapuato.com.mx/wp-content/plugins/super-forms/uploads/php/files/ed29958af8bf565b27b791027f282b90/zilisuvarufu.pdfIn PDF document text
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/c26huhhvtfdh06dkjvqfaavvb0/vibobujipibibakegez.pdfIn PDF document text
    • https://www.inter-tube.co.uk/wp-content/plugins/super-forms/uploads/php/files/95518314721ea678cfa2cbb56dd78dc8/mapoxavadupanunofa.pdfIn PDF document text
    • https://www.kcequipment.com.au/wp-content/plugins/super-forms/uploads/php/files/ad6c36bf9bab2d566534bdb334a3ef01/romifomuxagukuki.pdfIn PDF document text
    • http://musiconthebay.org/clients/2/26/269dd5bc96e197da989a8dccc71442af/File/55528268313.pdfIn PDF document text
    • https://capitaleny.com/wp-content/plugins/super-forms/uploads/php/files/8c32685d51c5d09e0a3cd2266a327a64/7879519058.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=geometry+completing+the+square+worksheet+answersPDF 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_off0000c1ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1FF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000da16.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA16 11400 bytes
SHA-256: 565a1c2d246f6738c3482403e2e93452ef7d03e685c8de57767a40bfed73f7cd
font_02_sfnt_off0000f48e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF48E 16236 bytes
SHA-256: 8972c2f1a9bb4adb8a0e5e7f4ef71b30de1c89183e2af5509b7ad66bd4520cc4