Malicious PDF — malware analysis report

Static analysis result for SHA-256 92f4f6746aed9f21…

MALICIOUS

PDF

73.7 KB Created: 2021-09-04 01:33:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 4e806b80cb582ee42535140c03f1122d SHA-1: ada81b111ceed72f614ade22817b9db5d45441a2 SHA-256: 92f4f6746aed9f21cd1095dcdb7b5ca35dec95ccfb9866cbd638e01a3fae17e4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics indicate the document functions as a link farm, pointing to numerous URLs hosted on potentially compromised or disposable domains. These links likely serve to redirect users to phishing sites or download further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 6

  • 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 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://evpersoneli.net/ev-personeli/file/jixobumujoxitu.pdf In PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/84806098449.pdfIn PDF document text
    • https://apskarota.org/userfiles/file/pipibinefokebugibubenuk.pdfIn PDF document text
    • https://lcd96.ru/wp-content/plugins/super-forms/uploads/php/files/335c38dbb5b99d475878ea3fa7530649/mukujome.pdfIn PDF document text
    • https://digicpictures.com/downloads/28844244395.pdfIn PDF document text
    • http://csc-0411.com/userfiles/file/20210830073041_yk3jbh.pdfIn PDF document text
    • https://fwullong.com/upfiles/editor/files/jurexiwemujuvukuj.pdfIn PDF document text
    • http://caycanh.vn/images/fck/file/lalavu.pdfIn PDF document text
    • https://ylwlgwadmin.ylwl.cn/upload/files/82983869502.pdfIn PDF document text
    • https://nhatngudongkinh.com/upload/ckupload/files/14465333660.pdfIn PDF document text
    • http://mikllc.mn/uploads/files/tuvelefetinegilor.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/9kbuhee64u2h4j0l7j3r3me1i0/kinolefelomokafalewarep.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092bda494e73---satipiwavunuxifotu.pdfIn PDF document text
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/0f2e448b173bee49fff6f9593f499601/lusenukibig.pdfIn PDF document text
    • https://takarasushimn.com/userfiles/files/tusutapulopew.pdfIn PDF document text
    • http://myboydfamily.com/clients/7/7f/7f513a2250c12de81a70a6735749c289/File/wejuroposamafivu.pdfIn PDF document text
    • https://sitebyside.ru/wp-content/plugins/super-forms/uploads/php/files/40895697fe4d7df909d37dbe79f2449d/31565217891.pdfIn PDF document text
    • http://watdoenwevandaag.nl/upload/linoruda.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=patriots+schedule+2019+pdfPDF 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_off0000bb0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB0F 11176 bytes
SHA-256: 11633d04d210d0cd38d1a72d2a11a1f093279e2147ff1d2f95a65342df1237b0
font_01_sfnt_off0000d569.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD569 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ed7b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED7B 17240 bytes
SHA-256: a33a84d0217d751a9f83337e1e5f5b9bce3352be979a405ce8179ca3bd1485ca