Malicious PDF — malware analysis report

Static analysis result for SHA-256 92e6a0504cf23c69…

MALICIOUS

PDF

85.0 KB Created: 2021-05-30 22:31:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 6f2393a3df85bf3fd85279144ae50da1 SHA-1: 5aecb93e76f0ed60a43dc976b966552eff0b0348 SHA-256: 92e6a0504cf23c697e8eb04502ed92498f756e98f720753308724cda1a52faed
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of external links, many pointing to disposable domains and employing UTM parameters, indicative of a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or distributing further malware. The document body is heavily obfuscated and contains metadata suggesting it was generated by wkhtmltopdf, not a typical document authoring tool.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://druttle.ru/123?utm_term=fallen+enchantress+legendary+heroes+game+guide PDF link annotation
    • https://gasibikame.weebly.com/uploads/1/3/2/8/132814219/8719285.pdfIn PDF document text
    • https://vuzabevewipa.weebly.com/uploads/1/3/6/0/136087677/7495353.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4465392/normal_60331986d4170.pdfIn PDF document text
    • https://wupizesave.weebly.com/uploads/1/3/4/5/134581048/c02b9f0947.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4484375/normal_6069475db6835.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4458145/normal_5fdb0ed938b0f.pdfIn PDF document text
    • https://mizefubu.weebly.com/uploads/1/3/4/6/134637235/4377345.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489977/normal_5fd29024ac104.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380682/normal_60184c75cec37.pdfIn PDF document text
    • https://tipovasikuvo.weebly.com/uploads/1/3/4/0/134041160/banibugiwufejivu.pdfIn PDF document text
    • https://fifosekula.weebly.com/uploads/1/3/4/0/134041306/jesotajukuzokufirexu.pdfIn PDF document text
    • https://jizojalagakamu.weebly.com/uploads/1/3/4/8/134886497/a8ffac8cd480.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/59851974-0ff0-46b7-8d85-d3c3e147d912/83644699752.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/71040934-0aeb-4e66-99ad-683cdc3df09f/95268482629.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d7abaed6-31f5-4824-a952-cd572ed3cb3e/longman_dictionary_of_contemporary_english_5th_edition_ldoce5_with_crack.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a6ec4b80-b08e-4537-994e-a727f1bf3cee/olson_mancur._1965._the_logic_of_collective_action.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bd91e9ca-5622-4bb8-9ca9-f05c62bf48f7/74182592019.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4bd17bea-6875-45de-b8db-1a06884695cb/gadebaruzivotefelok.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4a28aa61-bc01-4edd-a219-1405d2834532/24667892746.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9e4cb3f7-e555-455b-9996-732a71b21b53/dell_optiplex_7010_memory_replacement.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_off00010df7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DF7 5412 bytes
SHA-256: 04c47737114b44f1c1babde6bf3e33c1dd4eff98f7f75ff619b8590725b83807
font_01_sfnt_off0001203a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1203A 11148 bytes
SHA-256: 7c91f404de5bf05ceea1a64cd0731fd9122bab8dd2ebc5f092625118be6c33d9