Malicious PDF — malware analysis report

Static analysis result for SHA-256 b19bbd41168c327c…

MALICIOUS

PDF

83.4 KB Created: 2021-09-14 00:35:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 00b09d7f81ad3153434a8e058a4586b6 SHA-1: e0c101f9b10691aa2a82221cf137b201a6b8d641 SHA-256: b19bbd41168c327c6169bdb01bc12bd3e7917410bb4c39d197c1e77fa418010c
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ClamAV as Pdf.Phishing.Trojan and ML classifiers indicated a high probability of maliciousness. It contains numerous embedded URLs, many pointing to disposable domains, characteristic of a link farm used to distribute malicious content or phish for information. While no scripts were explicitly extracted, the PDF structure and heuristic firings strongly suggest it's designed to lure users to malicious external sites, likely via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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 http://xn--80aafjbawrcdgsodbdciig4a5v.xn--p1ai/pict/file/98193840603.pdf In PDF document text
    • http://webinaris.biz/ckfinder/userfiles/publics/files/todebavedisodozowevesoto.pdfIn PDF document text
    • https://anakaygame.net/calisma2/files/uploads/vuxasori.pdfIn PDF document text
    • https://rmp-traueranzeigen.de/cms/files/48609826422.pdfIn PDF document text
    • http://mybed.tw/uploads/files/202109050324285269.pdfIn PDF document text
    • http://www.a-fairys-choice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612ee4224f49c---78518845389.pdfIn PDF document text
    • http://cerezolorente.com/files/cerezolorente/_repo/file/gulotopezimunixuvodorop.pdfIn PDF document text
    • http://morakothotel.com/file_media/file_image/file/kikelosusifajej.pdfIn PDF document text
    • https://www.fyna.com.au/application/third_party/ckfinder/userfiles/files/tetudezojavotux.pdfIn PDF document text
    • http://umffz21.ru/admin/ckfinder/userfiles/files/93209310062.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fdf0e4569a---kubamakinojewu.pdfIn PDF document text
    • http://doorsatyrau.com/ckfinder/userfiles/files/9868717901.pdfIn PDF document text
    • http://usa-ex.com/images/blog/file/pizogerizerixikenojixov.pdfIn PDF document text
    • http://poslovniimenik.net/firme_data/files/33756120105.pdfIn PDF document text
    • https://www.bussmann-tiefbau.de/ckfinder/userfiles/files/zezowulot.pdfIn PDF document text
    • http://steakpluspizza.us/userfiles/file/60539127782.pdfIn PDF document text
    • https://prosaison.fr/userfiles/files/tipumejotupevuxenegu.pdfIn PDF document text
    • https://www.sibirprokat.ru/ckfinder/userfiles/files/3616826226.pdfIn PDF document text
    • http://bigdoughpizza.com/uploads/files/koxiturajitonotuw.pdfIn PDF document text
    • https://toppelletmachine.com/d/files/jasumira.pdfIn PDF document text
    • https://markyatirim.com/resimler/files/92803334623.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=airdrop+app+androidPDF 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_off0000e35a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE35A 9924 bytes
SHA-256: d976c5a8485e652c34a672af6d5b7aaca1bf2d48456f83a666d28aa181eec160
font_01_sfnt_off0000f93a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF93A 18244 bytes
SHA-256: b69f25a49ae430a08263a0e084e4abc156afe444e3629c93ddc46ad0c6381d66
font_02_sfnt_off0001287f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1287F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1