Malicious PDF — malware analysis report

Static analysis result for SHA-256 98be0a6a987acc8a…

MALICIOUS

PDF

92.4 KB Created: 2021-03-11 21:39:37 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-07
MD5: ec0d23c7aeba7fb5f51086a1f8181a3a SHA-1: 6924f01fac99fc63f33325865ca17e9897c68a20 SHA-256: 98be0a6a987acc8ad04d8bf355dc7bfe6bb75335a45326c8a5b9d7f9f573bcd0
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links pointing to various domains, many of which appear to be disposable hosting. The heuristic PDF_SEO_LINK_FARM indicates a link farm strategy, and the ML classifier and ClamAV detection strongly suggest malicious intent. The embedded URL 'https://nipisod.ru/wix?keyword=my+programming+lab+answers+java+chapter+6' is likely part of this SEO strategy to attract traffic.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://nipisod.ru/wix?keyword=my+programming+lab+answers+java+chapter+6 PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4487413/normal_60118a0ee786c.pdfIn PDF document text
    • http://electrumwallet.buzz/yahoo_mail_attachment_errorc5cnw.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4457839/normal_6014d5340be5e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403131/normal_6037b20f8c9da.pdfIn PDF document text
    • https://cdn.sqhk.co/dewavasese/Wifgh1u/dialga_gx_rainbow_rare.pdfIn PDF document text
    • http://sayseedokg.com/nenaxerevabebekivufapoi40b7.pdfIn PDF document text
    • https://mapokelamoda.weebly.com/uploads/1/3/1/8/131856574/zuzopipisimuwutanu.pdfIn PDF document text
    • http://chambreapp.xyz/fawosobuv51okr.pdfIn PDF document text
    • http://azakalaza3.xyz/canine_spondylosis_laser_treatmentxg604.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4394060/normal_5ff419b1a43a1.pdfIn PDF document text
    • https://ropexosuwewi.weebly.com/uploads/1/3/1/3/131380205/0bd0432fd1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4451355/normal_601fd0812166c.pdfIn PDF document text
    • http://xizerunax.scienceontheweb.net/chernobyl_disaster_facts.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4468537/normal_603f41646a65b.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4406241/normal_5fec8c41be63a.pdfIn PDF document text
    • https://ribofefafuf.weebly.com/uploads/1/3/4/7/134770843/jukunutova_xinumo_xewipepejekep.pdfIn PDF document text
    • https://cdn.sqhk.co/zudilubal/VWQgjER/39346155542.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4486045/normal_6013f04906a93.pdfIn PDF document text
    • https://mitivowa.weebly.com/uploads/1/3/1/6/131607237/6127030.pdfIn PDF document text
    • http://cosmicgig.com/sony_ht_ct780_specs70rkz.pdfIn PDF document text
    • https://cdn.sqhk.co/reparepoki/iiCIkc3/the_new_gate_schnee.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://rupesujutiwu.myartsonline.com/54480723355.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011cef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CEF 5976 bytes
SHA-256: 7dfd913af7a648432dc55aefc32e6f8235041f3a5c4a0fd36c3ff10a1e04e2e9
font_01_sfnt_off0001314c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1314C 16732 bytes
SHA-256: f3a8866f96d5b48563c52a8dabad04a89cb2dd9f1d529af6c1d59646becee5ed