Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac3c51a3784465d9…

MALICIOUS

PDF

84.9 KB Created: 2021-09-18 02:47:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 8bb04f842368972709c51109948acc86 SHA-1: 8b98b2f1dbf46afdf82cd5dac825c7c6967e8cf0 SHA-256: ac3c51a3784465d9465f1632bbea39f368bfc1283c2d4012af8e6e727beedc7b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous links to external PDF files hosted on various domains, suggesting a link farm or redirection mechanism for distributing further malicious content. While no scripts were explicitly extracted, the PDF structure and the presence of many external links point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://remoteyourstaff.com/calisma2/files/uploads/tadiwukivefo.pdf In PDF document text
    • http://meetburgerusa.com/uploads/files/48885722588.pdfIn PDF document text
    • http://assisdrive.pt/userfiles/file/natanudogaradisin.pdfIn PDF document text
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/f69ebe9271a7639c666434837345530a/wezovumidisigawalusirefu.pdfIn PDF document text
    • https://turdv.ru/SITE/files/editor/file/739499111.pdfIn PDF document text
    • https://clubon.top/uploads/files/tirulirijigumedazotur.pdfIn PDF document text
    • http://rsentco.com/upload/file/6611169254.pdfIn PDF document text
    • http://pjteam.hu/uploads/pofirutudevijolewoditas.pdfIn PDF document text
    • http://hc6999.com/userfiles/files/rabukepetepoluregewiku.pdfIn PDF document text
    • http://trans-serwis.com/userfiles/file/53860462094.pdfIn PDF document text
    • http://espicycooking.com/files/file///tutudemufofugaxowox.pdfIn PDF document text
    • https://hasekei.jp/userfiles/file/52213014415.pdfIn PDF document text
    • http://kcntanduc.vn/img_duhoc/files/93800114896.pdfIn PDF document text
    • https://www.scmsgroup.org/ckfinder/userfiles/files/75157403170.pdfIn PDF document text
    • https://fminterativa.net/cms/plugins/ckfinder/userfiles/files/rivujukukorijogedofiliroj.pdfIn PDF document text
    • https://euforbiabulgaria.com/uploads/pages/files/gupovoluta.pdfIn PDF document text
    • http://stin-verdon.fr/assets/Image/files/12264188794.pdfIn PDF document text
    • http://www.c-l-r-p.com/admin/ckfinder/userfiles/files/pusomebubulanepizis.pdfIn PDF document text
    • http://daiichigroup.net/uploads/news_file/97973336286.pdfIn PDF document text
    • http://golfvillageonline.com/userfiles/file/94832432399.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144cfe998a18---27411982255.pdfIn PDF document text
    • https://peiitw.com/Upload/ckeditor/files/kadok.pdfIn PDF document text
    • http://agroanaliz.by/upload/editor/files/japofawumoduxisesiviraj.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=hamlet+first+soliloquy+literary+devicesPDF 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_off0000e96e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE96E 10948 bytes
SHA-256: 8eebb0db97eb62d0a85210712ffeaf126cce581e6b46ee8c3a7d6e896255ed84
font_01_sfnt_off000102a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102A2 16864 bytes
SHA-256: 953a5f85074290148b27554e67ac86ba386d4dfd493286f396656748acefca00
font_02_sfnt_off00012e0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E0D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1