Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5596fc3b08c8145…

MALICIOUS

PDF

84.4 KB Created: 2021-09-17 03:50:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: c6936bb159b78fccfa86ec8040241392 SHA-1: b77d85a580018e6bd884e1f926a51c7bc7b11f22 SHA-256: f5596fc3b08c8145a5d8ba9cd177db80d0df6086afb68a13b69ea7f7342ca18e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs pointing to a link farm, suggesting a phishing or malware distribution scheme. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a pattern of using disposable hosting for these links. No scripts were extracted, but the structure and URL patterns are indicative of a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://hongmao.tw/uploads/files/202109061216524063.pdf In PDF document text
    • http://gutachterbewertung.de/userfiles/file/47768330913.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614146aee0962---guzuwojudog.pdfIn PDF document text
    • http://isystemlab.com/admin/ckfinder/userfiles/files/bujusutubul.pdfIn PDF document text
    • http://xn--82cac8d3ajrc0gd0bo4a7nf3qg.com/userfiles/files/buzolojiposiwesu.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613172b16cc6c---datisevibupirikolev.pdfIn PDF document text
    • http://deborahkay.com/ckfinder/userfiles/files/suwagimiguronukux.pdfIn PDF document text
    • http://engcaphone.com/_UploadFile/Images/file/7689443067.pdfIn PDF document text
    • http://760_709737661.mildmedia-dev.eu/uploads/userfiles/files/93854952959.pdfIn PDF document text
    • http://box8websites.com/ckfinder/userfiles/files/xaseramugofodapiw.pdfIn PDF document text
    • https://bengalroys.com/ckfinder/userfiles/files/wunukoridakut.pdfIn PDF document text
    • http://matrix-corporation.com/upfiles/editor/files/16231912740.pdfIn PDF document text
    • http://minerva-collection.net/files/files/33159804670.pdfIn PDF document text
    • https://sibois.eu/userfiles/file/mumizeger.pdfIn PDF document text
    • http://myhomeinparis.com/userfiles/files/xuxat.pdfIn PDF document text
    • http://studiotecnicomartani.eu/userfiles/files/38953565539.pdfIn PDF document text
    • https://reklama71.ru/upload_picture/21181484006.pdfIn PDF document text
    • http://cassotech.nl/site/data/ws/files/fasikemereja.pdfIn PDF document text
    • http://twtipa.com/upfile/files/2021/09/10/jatosuka.pdfIn PDF document text
    • https://adian.eus/files/galeria/files/70448034790.pdfIn PDF document text
    • https://hram-uspeniya.ru/ckfinder/userfiles/files/namemuluxerakatagubegoz.pdfIn PDF document text
    • http://baodieptailor.com/uploads/2021-09-12/images/files/18356213752.pdfIn PDF document text
    • http://www.pro9apps.com/app/webroot/files/uploadimagesfile/gomug.pdfIn PDF document text
    • http://jwconsult2005.com/file_media/file_image/file/maxaxub.pdfIn PDF document text
    • http://fanghsin.com/uploads/files/202109161006492274.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=screen+share+android+phone+to+macPDF 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_off0000e427.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE427 17916 bytes
SHA-256: 71000234c7630561f055a5c34c818fc7cbaa966e901a468ab2aa6d3893def7db
font_01_sfnt_off00011318.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11318 10808 bytes
SHA-256: de03b47326860f41f66cc1430df8462620fb8f32356ff926b35350124b88b5f8
font_02_sfnt_off00012bc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BC5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1