Malicious PDF — malware analysis report

Static analysis result for SHA-256 4f465aec4af485f3…

MALICIOUS

PDF

79.9 KB Created: 2021-04-09 22:18:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 1cecbf387ec0bb6cd3d545be0cbb0b17 SHA-1: 1f31eb09b31c8cbef1c82497cb337be33f8a1b60 SHA-256: 4f465aec4af485f301e929ec80326dfd090acd5d65d54ae263e56cbd8aeedc3c
186 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. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://mezovuduw.ru/strik?utm_term=mendeleev+lab+of+1869+cards+answer+key PDF link annotation
    • https://dapunilak.weebly.com/uploads/1/3/4/5/134506399/688c2501.pdfIn PDF document text
    • https://voluwunuzusiju.weebly.com/uploads/1/3/1/4/131452861/rogumeri_ritegesoven_fajevezuw_zixukizasiz.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379736/normal_6034ce4f1bdac.pdfIn PDF document text
    • https://dexixafavako.weebly.com/uploads/1/3/4/3/134348567/xapexe.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4388276/normal_5fe05d2b0fbb6.pdfIn PDF document text
    • https://gavaxavudo.weebly.com/uploads/1/3/4/5/134581950/bikotulinubefige.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4490961/normal_5fe46491eeb57.pdfIn PDF document text
    • https://mosejibufo.weebly.com/uploads/1/3/4/4/134437632/sajafogosuj.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4452376/normal_60567c67abf70.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4471686/normal_6068a37919eba.pdfIn PDF document text
    • https://pejegenipejixe.weebly.com/uploads/1/3/4/8/134848799/pujidugimawa_sogadod_muxulowo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367308/normal_606dc16a1d6dd.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4458849/normal_5fe620bdbfac7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426688/normal_60199e63d2070.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385847/normal_603b5fddb91b9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415531/normal_60645242eb8d7.pdfIn PDF document text
    • https://kakujaboregoj.weebly.com/uploads/1/3/5/3/135341432/a7d464f.pdfIn PDF document text
    • https://modemogip.weebly.com/uploads/1/3/0/7/130776314/ac3e804e54db1.pdfIn PDF document text
    • https://siwusoxol.weebly.com/uploads/1/3/4/5/134584737/c7c4e978d9d.pdfIn PDF document text
    • https://gedexezesojefib.weebly.com/uploads/1/3/4/6/134666283/6574949.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://8acf0fc4-2da8-4686-9788-d7840b5449fc.filesusr.com/ugd/fab691_abac247c6e9d44d9967f2565f512ee39.pdf?index=trueIn PDF document text
    • https://c538924d-9290-4e35-808b-5013ecaac822.filesusr.com/ugd/047ea9_01f93b77f37f40a4aefbaadf72318f36.pdf?index=trueIn PDF document text
    • https://4dd4a32c-aced-41d2-87e6-7ff9ca8080d7.filesusr.com/ugd/6d6f33_3aec7d1c9f9f4f32a8a8e79b63ac4a7c.pdf?index=trueIn 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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f3b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3B8 6036 bytes
SHA-256: bb92a99dff3121defd7cb834ca3e204794b7bfa08da40c548730fffd13d41577
font_01_sfnt_off0001087c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1087C 11944 bytes
SHA-256: 9256e47c6c2e63aa82cfab8788f7ccc160e1a8efdaf3e2048c074b350e3c6212