Malicious PDF — malware analysis report

Static analysis result for SHA-256 dfa3c099f380c250…

MALICIOUS

PDF

82.7 KB Created: 2021-09-05 01:46:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: f5eb2b205f2b8e6c297aea30ee71867f SHA-1: 6526fefc8076315338fc2a33c87de95726ee29dd SHA-256: dfa3c099f380c250c7e62b58f1560e797ffb8b1e3a51b3f23113ce62a2a3a777
156 Risk Score

Malware Insights

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

The PDF document contains numerous embedded URLs, many of which point to compromised or disposable domains, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of multiple external URIs and link farm heuristics further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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 http://suurelepa.ee/data/file/napuripitarenipox.pdf In PDF document text
    • http://industrialdevices.in/uploads/14023093888.pdfIn PDF document text
    • http://chonburi33.com/userfiles/file/67212987979.pdfIn PDF document text
    • http://chinajnbt.com/images/upload/File/zimepepafuxiji.pdfIn PDF document text
    • http://parmalab.it/userfiles/files/vekosekimoj.pdfIn PDF document text
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/f55aa5c761488208e788d95cbe64479e/97266561571.pdfIn PDF document text
    • http://mail-ex.net/userfiles/file/57541137893.pdfIn PDF document text
    • http://pbsdeltarho50events.org/clients/d/dc/dc3fcb918f61c9276c5829b035df2abc/File/75227159353.pdfIn PDF document text
    • http://jedzenie365.pl/ckfinder/userfiles/files/99204828313.pdfIn PDF document text
    • http://medi-sen.com/files/files/veraxatunivu.pdfIn PDF document text
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096a880c83e1---4124667018.pdfIn PDF document text
    • http://33podarka.ru/pictures/files/jefilemak.pdfIn PDF document text
    • https://dovolena-jiznicechy.cz/uploads/93584696443.pdfIn PDF document text
    • http://termosystem.pl/userfiles/file/85397771621.pdfIn PDF document text
    • http://www.redactordecontenidos.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160bcf31245fa6---nenuv.pdfIn PDF document text
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16121ce3e2b482---91257176824.pdfIn PDF document text
    • http://chiangmai-clean.com/user_img/files/38034020490.pdfIn PDF document text
    • http://area100impianti.it/userfiles/files/8062101440.pdfIn PDF document text
    • http://travisreunion.com/clients/1/1d/1d9c560ef9ee6310b862f4c9d288d7bd/File/gesevo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=phlegmon+diffus+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_off0000e039.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE039 10688 bytes
SHA-256: 413098c30641d5c89aad589919e54d8029821e82158722695c5d78386fd2fe6b
font_01_sfnt_off0000f841.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF841 17888 bytes
SHA-256: ca9161bdf7834de37329ea77e5c9c25c4c926b286af03b729b2c8b83afa3430b
font_02_sfnt_off0001260c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1260C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1