Malicious PDF — malware analysis report

Static analysis result for SHA-256 1821ccfa668526b3…

MALICIOUS

PDF

75.5 KB Created: 2021-09-30 12:44:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 0e4acbbb4cd3422bdff1c382f634a22e SHA-1: 9359d0bf7887399086897ccf91e227c63586c9b9 SHA-256: 1821ccfa668526b3d6ff31ecaeb6a1a2c091403d8bb2b70c72e51939be21bf6b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs pointing to disposable domains, indicative of a link farm designed to host malicious content or phishing pages. The ClamAV detection and ML classifier strongly suggest malicious intent, specifically identified as Pdf.Phishing.Trojan. While no scripts were explicitly extracted, the structure and URL patterns align with common phishing and malware distribution techniques, likely leveraging PDF vulnerabilities or social engineering to redirect users. The presence of 'utm_term' parameters in some URLs suggests tracking or campaign-specific lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://coretry.ru/uplcv?utm_term=speed+post+kanpur PDF link annotation
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16152f893a1203---94872692348.pdfIn PDF document text
    • http://www.cerel.eu/images/wyswig_images/file/93770118237.pdfIn PDF document text
    • http://isdoor.ru/uploads/files/2382280249.pdfIn PDF document text
    • http://kosmonautika.ee/ckfinder/userfiles/files/85330218675.pdfIn PDF document text
    • http://xn--9w3b11kh5l.com/ckupload/files/11936796880.pdfIn PDF document text
    • http://aedelsur.com/contenido/files/22065712342.pdfIn PDF document text
    • http://bigyikesmedia.com/home/xtremweb/public_html/consultinstitute/web/upload/files/22452414157.pdfIn PDF document text
    • http://ylplj.com/ckfinder/userfiles/files/verutow.pdfIn PDF document text
    • https://tranthachcaodanang.com/uploads/image/files/dekatisaguf.pdfIn PDF document text
    • https://adverto.ee/userfiles/file/bebule.pdfIn PDF document text
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/161500b48c0f8c---zazafafikisuzuvow.pdfIn PDF document text
    • https://sergiomauri.com/images/file/31608909490.pdfIn PDF document text
    • https://openkomm.yussfone-crm.com/userfiles/file/tenusiwabimimakixozalelo.pdfIn PDF document text
    • https://zapret-rf.org/web/img/podborky/files/57565528148.pdfIn PDF document text
    • http://ivankotov.ru/img/lib/file/59053169083.pdfIn PDF document text
    • http://italiangreyhound.pl/img1/userfiles/file/wovonadofasixi.pdfIn PDF document text
    • http://www.klimavill.com/data/editorfile/87098900627.pdfIn PDF document text
    • http://stihoplet.by/upload/editor/files/79575186878.pdfIn PDF document text
    • http://soskuwait.com/outscapes/admin/ckeditor/uploads/ck/files/87406584440.pdfIn PDF document text
    • https://horizontire.com/userfiles/file/60806784319.pdfIn PDF document text
    • http://www.radanhorse.com/resource/files/50087983341.pdfIn PDF document text
    • https://argumentua.com/i/file/mimumoborag.pdfIn PDF document text
    • https://burlingame.com/wysiwygfiles/file/fufukobonoxufusanep.pdfIn PDF document text
    • http://xmzhj.com/UserFiles/file/67472220353.pdfIn PDF document text
    • http://zonweringbelgie.be/ckfinder/userfiles/files/jagitadiforapuzogakom.pdfIn PDF document text
    • 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_off0000bc8e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC8E 20172 bytes
SHA-256: d1d3da982b25017e1fa925328163f4cea4e9b2a23869dfb1b4fa161ad275dcec
font_01_sfnt_off0000f03f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF03F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010856.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10856 10516 bytes
SHA-256: d74a6379430fae9e88de4a92467fb37c506a330c20420ca84bc7ee824635c540