Malicious PDF — malware analysis report

Static analysis result for SHA-256 a365652a69c04fc2…

MALICIOUS

PDF

158.8 KB Created: 2021-06-11 08:16:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 18e637f43286f07b39fc36deeea9f98b SHA-1: 77487189462332058f1f4ab6b5a7103ae51247c0 SHA-256: a365652a69c04fc2cf779ab2c5f6703189b5f35963d2755c226cc1351fdf558a
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple compromised WordPress sites and disposable hosting domains, likely for phishing or malware distribution. The embedded URLs, such as 'https://inwebjor.ru/uplcv?utm_term=henry+the+stickman+infiltrating+the+airship', are designed to lure victims into clicking through to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://inwebjor.ru/uplcv?utm_term=henry+the+stickman+infiltrating+the+airship PDF link annotation
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa7f52e63a7---62261597232.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/761493fb85e3db3f4b8ef48e77a1379d/peperefazeko.pdfIn PDF document text
    • http://btc-ltd.com/upload/file/xamaduzegowoziraw.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/qf3ukacqul53cl0kqjrhk0btg5/dozowarovesadinuw.pdfIn PDF document text
    • https://www.acetechnology.co.in/wp-content/plugins/super-forms/uploads/php/files/up7g7gitdcq9khheqca5tc4343/8930532947.pdfIn PDF document text
    • http://chnli.tw/CKEdit/upload/files/3195322496.pdfIn PDF document text
    • http://phantasos.org/userfiles/file/57875061993.pdfIn PDF document text
    • http://veraschwemmle.de/fckdata/file/68404090687.pdfIn PDF document text
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/07a44a2b55e62032763e6d4d44a02d30/lipasu.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609b4a1d4915d---64020285097.pdfIn PDF document text
    • https://sygimportaciones.com/wp-content/plugins/super-forms/uploads/php/files/qpufbdt8u8kujfre4jbu3itio9/wimedamobetowotow.pdfIn PDF document text
    • https://aprilboya.com/userfiles/file/bikozuvipusejuw.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1609e6496aebc7---jawogokonipuvawif.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dd2e642f64---40864261775.pdfIn PDF document text
    • http://af.ssla.ru/images/fornews/files/dujasesag.pdfIn PDF document text
    • https://area34.info/wp-content/plugins/super-forms/uploads/php/files/e4u9lecs3gre9u3bv8h5a0p575/68035564927.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off00020d4d.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x20D4D 10768 bytes
SHA-256: 207ce2bb2a68a055ffcc934ecf0bf80a17597b5ee645a9038a7903e166e379e6
font_01_sfnt_off00023122.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x23122 5556 bytes
SHA-256: cd9d8834d74725e99404ad8b484fc1562156e492ea69e365b7782b7d1af8f0f2
font_02_sfnt_off000243ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x243EE 11900 bytes
SHA-256: 16e281a983a1e28818de0dac63e4aa8f9614509a250d73083f337ace6784484f