Malicious PDF — malware analysis report

Static analysis result for SHA-256 23b591d5cb3cb44a…

MALICIOUS

PDF

69.7 KB Created: 2021-10-01 02:45:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 3b0f8a9fc030c861498fd37afc32fa6a SHA-1: a1d0697c14df47dc6d3fa3a62be7de62ab3be1a1 SHA-256: 23b591d5cb3cb44a7b293567d15072754b28a4cee3bf59c6946454948bfc6b9a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs pointing to various domains, many of which are associated with link farms and potentially compromised content management systems. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests a deliberate attempt to obscure the final malicious destination through a network of redirecting links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://queure.ru/uplcv?utm_term=content+not+supported+text+message PDF link annotation
    • http://bellamy.tw/uploads/files/202109231401232354.pdfIn PDF document text
    • https://davidfauquemberg.com/home/fauquemb/david/bbdg_site/userfiles/file/zuzone.pdfIn PDF document text
    • https://fasleh.net/Files/files/99852076441.pdfIn PDF document text
    • https://negaratoto.com/contents/files/62718160758.pdfIn PDF document text
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614d00f27dde9---76403096737.pdfIn PDF document text
    • http://skisun.it/userfiles/files/vufugajixagem.pdfIn PDF document text
    • https://presentkompaniet.com/img/content/file/fepifafofivezipirunalulu.pdfIn PDF document text
    • http://jawarakreasi.com/file/voluforebaboxu.pdfIn PDF document text
    • http://jandenzobv.com/image_uploads/file/xumawefarisokaxijikatu.pdfIn PDF document text
    • http://lineshare.net/upload/files/20210905235654.pdfIn PDF document text
    • http://pxmonastery.org/CKEdit/upload/files/53990024544.pdfIn PDF document text
    • http://crestviewshopping.abwingsmd.com/uploads/files/48846228794.pdfIn PDF document text
    • http://globalroomplus.com/bot/ckfinder/uf/files/62589240043.pdfIn PDF document text
    • https://kvartira-zalog.ru/wp-content/plugins/super-forms/uploads/php/files/ff4a3034d3c38e3cf5728c187839e472/kalopinu.pdfIn PDF document text
    • https://www.potterycommercials.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614ddf5e231c0---94273209679.pdfIn PDF document text
    • http://melabo.com/upload/files/94861913480.pdfIn PDF document text
    • https://salwangurugram.com/files/rimajawuzunij.pdfIn PDF document text
    • https://ochronaskory.pl/pliki_user/File/miputegejarif.pdfIn PDF document text
    • https://ezastupitelstvo.sk/editor_uploads/system/files/lajof.pdfIn PDF document text
    • https://psystat.net/candyticket/uploads/page_images/files/gofukazo.pdfIn PDF document text
    • http://theseadiaries.com/ckfinder/userfiles/files/rogifirerunede.pdfIn PDF document text
    • https://relaxbotanika.cz/ckfinder/userfiles/files/36187843432.pdfIn PDF document text
    • https://educationindiajournal.org/ckfinder/userfiles/files/magosegek.pdfIn PDF document text
    • 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_off0000b1c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c9db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9DB 15232 bytes
SHA-256: fbf49587ffbfe086ddeabe7b51e48c9d28366acf7065489be450433758f5dfb6
font_02_sfnt_off0000f05c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF05C 10832 bytes
SHA-256: 24b132e3064ec169070cd85cf21788458d3d7c56974b5682c0de33cede1a9f7a