Malicious PDF — malware analysis report

Static analysis result for SHA-256 35815e26971502f4…

MALICIOUS

PDF

79.4 KB Created: 2021-05-02 02:54:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: 0b2db897bdce72a250648eb85485002a SHA-1: ae08999993f43ba287fb1ee9f4b7b9abe232798e SHA-256: 35815e26971502f4274810a584648d0d27bdf2f4f9930c109accae7350ef9e8d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The sample is a PDF document flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, with several pointing to disposable domains and acting as a link farm. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a high likelihood of this document being used for phishing or distributing further malware. No scripts were extracted, and the document body was heavily obfuscated.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 5

  • 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 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://kuzutuzo.ru/strik?utm_term=what+is+unique+to+western+australian PDF link annotation
    • http://xxlmature.site/it_kind_of_a_funny_story_music_list0wlwu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369904/normal_60329b34df13e.pdfIn PDF document text
    • http://medway24.com/ews_reservation_certificate_online_formqf5o7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4480895/normal_606c2124519df.pdfIn PDF document text
    • http://boderuj.iblogger.org/69351778887.pdfIn PDF document text
    • http://nukels.xyz/batimesefapakiwim9f70.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4497082/normal_60136c8f40127.pdfIn PDF document text
    • http://securespot.ru/6303183002itjek.pdfIn PDF document text
    • http://autobaff.xyz/68701014895xzquq.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4492246/normal_602f5f2143fe0.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4489994/normal_5ffa179dc7551.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://7d33af4c-acfd-4996-9436-348e89828b5b.filesusr.com/ugd/289672_01e107a95ce543dbb62173c7bd946c1c.pdf?index=trueIn PDF document text
    • http://fanuxifesuz.rf.gd/pifedefevasusovusudax.pdfIn PDF document text
    • https://s3.amazonaws.com/wamatasamegu/kajofitorodizujat.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/455a7a49-bf1f-4808-b64f-8276be0a9110/how_to_set_up_kindle_app_for_child_on_iphone.pdfIn PDF document text
    • https://s3.amazonaws.com/babuxufarizuxur/jowipi.pdfIn PDF document text
    • http://rileponabamel.rf.gd/singular_plural_worksheet_for_grade_3.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/aee464c3-f8c1-4d09-b02a-828b473f6e25/what_is_the_flying_dog_called_in_neverending_story.pdfIn PDF document text
    • http://vemusimovoxodan.rf.gd/lenema.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/31d8ddff-775e-45b0-bdcd-0a8abb831c8d/79619694588.pdfIn PDF document text
    • https://b5526579-b22d-45a0-8251-9885a72cf3eb.filesusr.com/ugd/0cd019_3c28160ce2fd4250abc6f9c23f4c24a3.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c21f20c5-7016-449a-aa3b-c4a5bb5e007d/how_many_carbs_are_in_a_mango_slush_from_sonic.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/579f16ec-39c6-468b-83c3-11c123e334e9/the_pleiadian_workbook.pdfIn PDF document text
    • https://6ada6c45-9e8d-4063-9633-40b9e375d9b0.filesusr.com/ugd/9a7afa_cbbcb09116cc4a31b041aa8286405f15.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/bisute/bewitched_tv_series.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_off0000f9df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9DF 5004 bytes
SHA-256: e5311a365911695fa98eac02055e09a79e9a65b2be0050e8ec20da7a40707f38
font_01_sfnt_off00010af6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AF6 10888 bytes
SHA-256: 0e8186677747a8e555122e0975aaf77eb8b67583eb5e529d8eb8fe118ff49033