Malicious PDF — malware analysis report

Static analysis result for SHA-256 90915860fe570e83…

MALICIOUS

PDF

85.5 KB Created: 2021-03-09 06:32:11 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 381c211ba554fac53c9af6b2118b1793 SHA-1: 59f14ee4fc7b0c5f1c3fb0b4c2b1dc4d1fb5386d SHA-256: 90915860fe570e8346595730ceff4198e054da639690d30528d7ea4108b9630a
194 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 and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://gimoguvi.ru/123?utm_term=allegiant+movie+300mb+free PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4460678/normal_6037ed1b12bfb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4468274/normal_602baa15e5e0a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4379384/normal_5ff8ce55a2ea5.pdfIn PDF document text
    • http://worameruvejaka.mywebcommunity.org/33410648930.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450511/normal_603f610562721.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4420030/normal_6046bc697a1c9.pdfIn PDF document text
    • http://bumumapa.mypressonline.com/what_to_the_slave_is_the_fourth_of_july_purpose.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393036/normal_5fdc109be37c9.pdfIn PDF document text
    • http://rating-bookmaker.ru/80615282113tstrj.pdfIn PDF document text
    • http://zikewexer.scienceontheweb.net/wajozogutogamulavoregofo.pdfIn PDF document text
    • http://playmarket-online.com/wifopabunitukubegos494n3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476140/normal_60340fb9d316b.pdfIn PDF document text
    • http://vodizurulenega.mypressonline.com/pomutusafitikibaditojunu.pdfIn PDF document text
    • http://fitnesspack.net/menu_ideas_for_dinner_party_of_4o6kai.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4386086/normal_601b303b4d664.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://0c2a99dd-71fd-4a0d-b96f-672cfa785c21.filesusr.com/ugd/515c54_1f87cc699770458d9d01c7398526f615.pdf?index=trueIn PDF document text
    • https://ba10d46a-d7c1-43af-8542-f1a50f31aa8a.filesusr.com/ugd/4dded2_2d55b2bd1fae4eea832df697aa44641d.pdf?index=trueIn PDF document text
    • http://jujobope.atwebpages.com/toro_sprinkler_valve_parts.pdfIn PDF document text
    • https://f039f7e9-c7fa-441d-bf3d-2f0e35d6be10.filesusr.com/ugd/80685d_0a8815afb615449fa4d9bfeebfad19bd.pdf?index=trueIn PDF document text
    • https://3568ea06-17fa-4787-91ae-86b9aa918cbd.filesusr.com/ugd/8ade13_f4194e70e5ee4242ac33513daba9a405.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
    • https://savannah.gnu.org/projects/freefont/In PDF document text
    • http://www.gnu.org/licenses/In PDF document text
    • http://www.gnu.org/copyleft/gpl.htmlIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f8b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8B0 6744 bytes
SHA-256: b29f9350a720d2da9dc50567d08c4a82684db1fcb28a47e3a5788345b392d808
font_01_sfnt_off00010995.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10995 5404 bytes
SHA-256: fffc2db297e44c998bce6cd03b0109ff423468a0f044bc1751eb380d6e2cf2f2
font_02_sfnt_off00011bf0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BF0 13168 bytes
SHA-256: 4cf1d630640531701b0a6c0be07f5e3d5d2b4b5c50f085519a7abb6df89e425c