Malicious PDF — malware analysis report

Static analysis result for SHA-256 3fd21ec49362b1a7…

MALICIOUS

PDF

79.6 KB Created: 2021-05-03 09:13:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: c1ec7d2f9af1a30f3c2feddc3117c5ea SHA-1: 22dbe68ebb530936a0f06fce8d73da9823fc26f2 SHA-256: 3fd21ec49362b1a7e33910501737d89d66dec0b734dd7ad608c70748b0b87cce
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which are hosted on disposable domains, indicating a link farm designed to direct users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the embedded URLs are the primary indicators of compromise.

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://golowaki.ru/strik?utm_term=pocket+guide+to+apa+style+7th+edition PDF link annotation
    • http://sallehq.xyz/azar_apk_mod_revdlhuajy.pdfIn PDF document text
    • http://lisolu.org/academic_calendar_laguardia_community_college_2020fu61f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422136/normal_60260b68e10a2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4378152/normal_6021fea82cec7.pdfIn PDF document text
    • https://fukokegoxa.weebly.com/uploads/1/3/4/4/134463136/f96b9fc.pdfIn PDF document text
    • http://docita.fun/barcarolle_guitarq5yd9.pdfIn PDF document text
    • https://dopovubejaxow.weebly.com/uploads/1/3/4/0/134017692/nakevazonimatodupali.pdfIn PDF document text
    • https://jojumevowe.weebly.com/uploads/1/3/4/3/134314985/ratijixebelefoj-wibobote-nonuwupo-gelifobefofuf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426828/normal_5fd7b551d382a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405639/normal_605beaabc135c.pdfIn PDF document text
    • http://pifadopagel.scienceontheweb.net/volaxofatebaza.pdfIn PDF document text
    • http://gayerkan.com/nakomalisagag3pyv.pdfIn PDF document text
    • https://kuwofepex.weebly.com/uploads/1/3/2/7/132740654/batewi-vozegevonutepo.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://a7da3e60-63c8-46c1-a846-eab7df628ed2.filesusr.com/ugd/bba345_dfda3eea33404431aefd2e49d4925b5a.pdf?index=trueIn PDF document text
    • http://tuwutexo.onlinewebshop.net/gopamamakadibuvi.pdfIn PDF document text
    • https://c81c1a69-aec6-471c-ac34-7a6800eafc69.filesusr.com/ugd/9ef1ea_e4240105ce01400c9f464a1781f58d96.pdf?index=trueIn PDF document text
    • https://878ee1be-828d-48b9-a24a-84283cf66a1c.filesusr.com/ugd/86936c_c3aefeb7cd89437ba3eb8a85c1ca95d8.pdf?index=trueIn PDF document text
    • https://ea64ff4c-51e6-4efc-8cc1-399682447901.filesusr.com/ugd/961f18_12a533463d85433c8143a5190282b0d7.pdf?index=trueIn PDF document text
    • https://36425c1f-c329-48aa-845d-1f8252cb45c8.filesusr.com/ugd/01d500_99035b85de9a409a99827c94f8c908d8.pdf?index=trueIn PDF document text
    • https://cb70cc59-2297-49c3-b7e2-2ac7e26e28d4.filesusr.com/ugd/4479ed_3c5717c043cf46dcbc4388a3abd62c3d.pdf?index=trueIn PDF document text
    • https://4647adb0-9c01-46a1-aef1-4380d5873f13.filesusr.com/ugd/edb4a7_9543bdece13e4a1199a59cad81c50ed2.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_off0000f876.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF876 5484 bytes
SHA-256: ad0030187250a17e7906f5601117f1a09606412a802102aa3830f3ef15e9b5c6
font_01_sfnt_off00010b38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10B38 10948 bytes
SHA-256: 1a3823eba84acf64c3c49d02cf2fb7b3965bdf5d017614a39156f15b4c54f632