Malicious PDF — malware analysis report

Static analysis result for SHA-256 a56f903a0bee9e9f…

MALICIOUS

PDF

74.9 KB Created: 2021-06-23 22:56:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-02
MD5: aad33958ba4e93346e18ddd1c9a0d7a5 SHA-1: 1f312aed37178305aab247161c731c6cf6f4aba2 SHA-256: a56f903a0bee9e9fc5f3854723b76206a20cc4b45387758e23ac43a43f1999ea
156 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://k-newsletter.com/ckupload/files/21190271960.pdf In PDF document text
    • https://stollerco.com/testingsites/advantage_aviation/assets/media/file/8632057339.pdfIn PDF document text
    • https://vieclamxaydung24h.com/upload/files/12634942501.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a034ab13572---ligegozoj.pdfIn PDF document text
    • http://richmediahouse.com/admin/uploads/file/nozoxudesef.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608135f994c51---49848566743.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f5cb5db9ca---natoxawudixamazena.pdfIn PDF document text
    • http://uyaviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b05dcc3b23d---vaxawefavunasunomoxodew.pdfIn PDF document text
    • https://maloneslandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3334892e2---kotikurebojel.pdfIn PDF document text
    • http://aihyang.com/userfiles/file/xupawedebezonitat.pdfIn PDF document text
    • https://floridainvestment.cz/files/file/73818777853.pdfIn PDF document text
    • https://www.frankreich-ferien.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1609056cf96ed3---67022997425.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1607df0982b31b---ludinofetew.pdfIn PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160a93fa675d92---56709556491.pdfIn PDF document text
    • http://kaowei.tw/image/files/20210611_014138.pdfIn PDF document text
    • http://srihemkuntsahibfgp.org/hemkunt/userfiles/file/7193023069.pdfIn PDF document text
    • http://acetuitioncentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1608f60f751bc1---48192510319.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/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=analise+financeira+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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e47c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE47C 5140 bytes
SHA-256: 0c66989accab735a6d9ea8327a4be2bfc0713d77e80ecfadf2dce087b05ec6a9
font_01_sfnt_off0000f60a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF60A 12884 bytes
SHA-256: 1a246846c4add48fd425f24dbc3425d0486218558d7dbd46119e195d070620f0