Malicious PDF — malware analysis report

Static analysis result for SHA-256 a84153d3098ae4c6…

MALICIOUS

PDF

106.1 KB Created: 2021-06-18 04:11:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 7c22f7ebd7383daa72aa0d392b36b9f8 SHA-1: 8b938b3ab05f098d6b89398ed9f64766227d55cb SHA-256: a84153d3098ae4c66dfbe13812a8136d9c75c0faa8bfff8cc9d4eae019ea96b0
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded links are indicative of an attempt to leverage external resources for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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 https://blindnow.com/userfiles/file/levazabokemowejerob.pdf In PDF document text
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/16083bbca90537---kagabipamujapumegaz.pdfIn PDF document text
    • https://www.eoluk.com/wp-content/plugins/super-forms/uploads/php/files/ck6iggk4fmfkohstq5nli27psj/69648476138.pdfIn PDF document text
    • https://agilitynd.com/wp-content/plugins/super-forms/uploads/php/files/69a9217942809cf94e1dade17d74390a/99481170139.pdfIn PDF document text
    • http://chemonova.com/FCKeditor/file/wasozosiko.pdfIn PDF document text
    • https://ferropula.hr/files/lumuvezebinefa.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608fec54819bb---53148465667.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075369c1ce8a---bibezebonilibifobitatix.pdfIn PDF document text
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/44f53c743cbacae4a2a76f1f65cee248/lupopez.pdfIn PDF document text
    • https://victorybear-info.com/userfiles/files/32672672711.pdfIn PDF document text
    • https://airbays.com/userfiles/file/ravidik.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/fa7ed9be3977c8239cf9ed594870faea/kunuxogew.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/1608a37c40a28e---jalikanufod.pdfIn PDF document text
    • https://levin-dent.ru/wp-content/plugins/super-forms/uploads/php/files/56cba364553e25a4333760b120a9fcec/77658825112.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=korean+regular+verbsPDF 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://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011064.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11064 21140 bytes
SHA-256: 6eb8c16669b496c4370176352902d081965426a360e48e1fe692a59801d1f874
font_01_sfnt_off00014e7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14E7F 5020 bytes
SHA-256: 73d6a38f52a59dabd79a84b7e2967f3e90f3e749b12f0dcf046ca4f55737059a
font_02_sfnt_off00015fb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15FB0 11164 bytes
SHA-256: 5d55c9b1e2a1085417d4204b50399fa3798e2905ece46f1713420635a3c164c7
font_03_sfnt_off0001862c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1862C 16060 bytes
SHA-256: ae97ebdbf5cb6679ee3ae7f6f8963da9ec2437ada1f672a33085bc8cbe806833