Malicious PDF — malware analysis report

Static analysis result for SHA-256 3dc71b1d76c2aad8…

MALICIOUS

PDF

74.4 KB Created: 2021-10-06 23:31:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: befbe2ecb493db4d56e2c086e84b6e35 SHA-1: fef2c26c803d748787baf1e9719853100ac80b74 SHA-256: 3dc71b1d76c2aad859a16a35dffafe5f8fcfbac67bc542e8a16b12f459a5e22e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as a malicious PDF by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to suspicious domains and are likely used to redirect users to phishing sites or download further malicious content. The PDF structure itself is also flagged as a link farm on disposable hosting, further supporting a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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://haltia.mx/sii/ckfinder/userfiles/files/ludabageg.pdf In PDF document text
    • http://wagnerpc.com/userfiles/files/43829287466.pdfIn PDF document text
    • http://strandedtattoo.info/file/wudavowuviziv.pdfIn PDF document text
    • http://hb-hospital.com/file_upload/fck_upfile/file/bokomenugidalewozo.pdfIn PDF document text
    • http://vrzion.com/data/userfiles/files/sujeginowufesov.pdfIn PDF document text
    • https://doublehaircenter.com/upload/ckfinder/files/mewoloduzivitaj.pdfIn PDF document text
    • http://www.themixchange.com/userfiles/files/87738829848.pdfIn PDF document text
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/1df420091fb9d3a407c2ac329a44e63c/puvesopaxokovobuzubosije.pdfIn PDF document text
    • http://www.hebrewforreadingcomprehension.com/content/5442445485.pdfIn PDF document text
    • http://kursadowicz.pl/Upload/file/30204970424.pdfIn PDF document text
    • http://www.anapharmata.hu/ckfinder/core/connector/php/files/45109475559.pdfIn PDF document text
    • http://archidaldegan.eu/userfiles/files/49174244660.pdfIn PDF document text
    • https://piphoto.tw/uploads/files/202109082059173566.pdfIn PDF document text
    • https://uleshuzatabc.hu/files/file/pupukikunaxemexeb.pdfIn PDF document text
    • http://orkoien.com/userfiles/files/24332511354.pdfIn PDF document text
    • https://ikra-ekb.ru/files/fckeditor/file/In PDF document text
    • http://bjerkelunden.org/content/files/userfiles/file///48496619717.pdfIn PDF document text
    • http://xn--rssx31a7tec6p.com/upload/userfiles/files/20210906225806.pdfIn PDF document text
    • http://sanmorales.es/userfiles/files/76316097979.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/guwenejezolex.pdfIn PDF document text
    • http://topenglish.sk/app/webroot/gallery/files/buvuwomakolugowawufo.pdfIn PDF document text
    • http://antansconstructions.com/ckfinder/userfiles/files/nariv.pdfIn PDF document text
    • http://quick-thailand.com/images/uploads/file/82303494757.pdfIn PDF document text
    • https://profix.fr/ckfinder/userfiles/files/buduxusupudojipovanekex.pdfIn PDF document text
    • http://vocal.bpv.su/content/files/files/36025067016.pdfIn PDF document text
    • https://cowichanseniors.ca/userfiles/file/teleremuku.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=types+of+anthocyaninsPDF 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_off0000c2de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC2DE 16200 bytes
SHA-256: 152c3df818367ad3bfe1c6b32b1f24736a76bc0aa6e429b3f262bece4393896f
font_01_sfnt_off0000ebb7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBB7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000103ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103CE 10508 bytes
SHA-256: 7c4b213699b2e7000d3e378a30f71edae8cbfed79252409bfb76c613e31955f7