Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5a078bd9bd1be06…

MALICIOUS

PDF

75.2 KB Created: 2021-09-17 00:38:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: ac70d14aa7af7e283265512a624029f9 SHA-1: bcf1c604f9fac02dd7fef142dbe50dcac511a217 SHA-256: c5a078bd9bd1be06efa6710746cdd1329a3cdceefb09078570f7af03fe68d4ec
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple links to external resources, including one identified as an algorithmically generated URL on potentially disposable hosting. ClamAV detected this file as Pdf.Phishing.Trojan, and ML classification strongly indicates malicious intent. The embedded JavaScript likely serves to execute malicious code or redirect the user to a phishing site.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://digicpictures.com/downloads/7966637200.pdf In PDF document text
    • http://nppgursaraijhansi.in/ckfinder/userfiles/files/13230770429.pdfIn PDF document text
    • http://fmdscu.net/userfiles/file/ludedofevulewosona.pdfIn PDF document text
    • http://ternovykh.ru/content/file/tozetulogepit.pdfIn PDF document text
    • http://wintec-samu.hu/uploads/files/deraw.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613207a4c0442---99733110621.pdfIn PDF document text
    • http://precisionsurgicalworks.com/alpha/ckfinder/userfiles/files/93597434410.pdfIn PDF document text
    • http://aj-freight.com/ckfinder/userfiles/files/81383659048.pdfIn PDF document text
    • http://studiomedicoveterinariobellucci.eu/userfiles/files/99281937645.pdfIn PDF document text
    • https://cleaner.pl/userfiles/file/sapubasogukekodun.pdfIn PDF document text
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613b01a8876b3---55122539315.pdfIn PDF document text
    • http://votava2.altrodesign.eu/ckfinder/userfiles/files/64737583431.pdfIn PDF document text
    • https://artcorner-fiberglass.com/userfiles/files/21767702929.pdfIn PDF document text
    • http://bookblog.kr/data/file/files/medizuxuvitowofiko.pdfIn PDF document text
    • http://fruhmann-elektrotechnik.at/moretuvapibutozubaliga.pdfIn PDF document text
    • http://js-space.de/userfiles/file/82576204736.pdfIn PDF document text
    • https://seikai.jp/free_images/files/92588572981.pdfIn PDF document text
    • https://golf-tout-terrain.com/publish/page/file/runisiko.pdfIn PDF document text
    • https://nguyenvanhuongloc.vn/app/webroot/files/images/pages/files/xulaxufak.pdfIn PDF document text
    • http://tsutae-f.com/js/upload/files/75115999103.pdfIn PDF document text
    • https://kotypsy.pl/ckfinder/userfiles/files/75334686491.pdfIn PDF document text
    • https://santa.my/images/users/00000000/files/43021271606.pdfIn PDF document text
    • https://idea-web.ro/app/webroot/files/userfiles/files/wevomodolug.pdfIn PDF document text
    • http://www.andreapondika.cz/file/puwudi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=antutu+benchmark+download+play+storePDF 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_off0000b374.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB374 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cb86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB86 22436 bytes
SHA-256: b4d32013507b37b4fd2ef32559d70a29d381e0684522ec6aa1799cd8dd9b6bac
font_02_sfnt_off00010365.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10365 11200 bytes
SHA-256: b929b64de35f06b0662ef8561cddf107476255006aa60186bb6ce214efac662b