Malicious PDF — malware analysis report

Static analysis result for SHA-256 2121e0120f137e08…

MALICIOUS

PDF

84.2 KB Created: 2021-06-15 11:27:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: e92c2cf4ac8cd3da8b97b82cae6d3df3 SHA-1: 386ace816c9cab62b0483cf486a2eea3dee56ddc SHA-256: 2121e0120f137e089d93a863d4514163043fa9048d6adee4529f5a32b9bffd4b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file is classified as malicious by ML and ClamAV, indicating a high likelihood of malicious intent. The document contains numerous links to compromised websites and disposable hosting, suggesting it functions as a link farm to distribute further malicious content. The presence of embedded URLs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicate the primary goal is to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://huntic.ru/uplcv?utm_term=class+10th+english+grammar+pdf PDF link annotation
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca37a3325e---lulewopalumig.pdfIn PDF document text
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/08cb777c891a6a5339a6391e63f92c3b/poluta.pdfIn PDF document text
    • https://csom.cz/wp-content/plugins/super-forms/uploads/php/files/681fe85dfcb5e4f32df38ba7680944f4/tanulisibedugekiwar.pdfIn PDF document text
    • https://mcq-exambd.com/app/webroot/ckfinder/userfiles/files/12891417865.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/16086d3c533bfb---kazepatawesewudimov.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16093f267e3bc3---kafatuwamoxefevewejazufa.pdfIn PDF document text
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/4on5kr4it5v2s41i04ldt95nkl/sebos.pdfIn PDF document text
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b40ee744b6e---lumox.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c4373218670---xozopuvojozotefurubovuje.pdfIn PDF document text
    • https://mannerfeltdesignteam.se/ckfinder/userfiles/files/nusiruwopimetukusolili.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acbcde36c12---rozezokexunu.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1607a71107d41f---49057338560.pdfIn PDF document text
    • http://esipro.fr/userfiles/file/78626164477.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e638.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE638 5552 bytes
SHA-256: 49ca034d35ca1e9e375dc67b6f26233a8bb278a3c724fb5491b1c51f7cfb5697
font_01_sfnt_off0000f8e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8E3 2676 bytes
SHA-256: 0a80cc866ab3705b719cff30790c1712fc18d54f38e193ee65e92b733afa98e0
font_02_sfnt_off00010478.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10478 12692 bytes
SHA-256: a33e0621e0bd2b616378f92bcf0e8b831d8624cdcc4be68671993d000e57446e
font_03_sfnt_off00012e19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E19 16204 bytes
SHA-256: 532315dfdc59b350d447ad91845dd8cc72a836e684f536ab9a4305dc5b53fb8e