Malicious PDF — malware analysis report

Static analysis result for SHA-256 aab9bd418f5c2e18…

MALICIOUS

PDF

80.6 KB Created: 2021-03-08 19:20:34 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-17
MD5: 5a51fbeb269d0198e73efc4922885f09 SHA-1: 5f6a7fca2af3e771b9d2a593874eae381d38253d SHA-256: aab9bd418f5c2e18649eac305df5692346db486b8de7c3def33a88195fb58f2d
244 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by multiple heuristics and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of embedded links, many of which point to a redirector infrastructure. The document body, though heavily obfuscated, appears to reference job opportunities, suggesting a phishing lure. The primary malicious IOC is the redirector URL which is likely used to deliver a secondary payload.

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://crophysi.ru/strik?utm_term=computer+operator+jobs+in+dubai+salary In PDF document text
    • https://cdn-cms.f-static.net/uploads/4424007/normal_602c170515ef3.pdfIn PDF document text
    • https://cdn.sqhk.co/tamejenonisi/fhhhbfp/labyrinthine_meaning_in_malayalam.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368762/normal_602ff5bad6aec.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4367622/normal_5fcafc28ac870.pdfIn PDF document text
    • https://cdn.sqhk.co/vapumojemov/Fhegghf/fifusekatadenedogoro.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4478127/normal_5fe512227c4d7.pdfIn PDF document text
    • https://cdn.sqhk.co/jalosemuv/VJjeIhg/evaluate_expressions_worksheet_4th_grade.pdfIn PDF document text
    • https://cdn.sqhk.co/wazafanez/thD9Dge/assistant_project_manager_salary_entry_level.pdfIn PDF document text
    • https://cdn.sqhk.co/ripowusaro/jbRij22/tutovarele.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/8011d0ec-1c24-48aa-9222-be3565ec9cb4/everlasting_god_new_life_worship_chords.pdfIn PDF document text
    • https://6acf0ca1-aa41-4771-8b91-54baff69ee7f.filesusr.com/ugd/7d1dc9_868207faf9e3494e82acfcb976ae8c79.pdf?index=trueIn PDF document text
    • https://5090c2af-253d-40c3-bfb7-942fc6db26b0.filesusr.com/ugd/0511f5_d9c3e24bfa59461c92001665253b7390.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/79b0db76-6e75-4620-86a2-80487208d1bd/wimiwozezaluzubafumekug.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0fa354b7-b346-43b9-beb2-44fd8d45c728/sorcery_points_conversion_5e.pdfIn PDF document text
    • https://e809654a-a95b-4dbc-a338-24085255a2f8.filesusr.com/ugd/1b6cec_5b5ef8e60eab460b97aa2dd6692a9213.pdf?index=trueIn PDF document text
    • https://fc06435f-e709-4c80-b59d-96fa470c1a13.filesusr.com/ugd/bdc04d_e300cb41b51d4308b739f14fa6b32845.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/cb476ea5-7e8a-4d64-bc4b-7e9a73bba70e/turtle_beach_xp400_xbox_1.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1b2be2eb-8846-4066-bc76-703c2f821304/washington_state_weather_in_may.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7d0a4d67-6d79-4ed4-a236-23eff8f62a40/what_does_lysis_mean.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/59a953d0-c568-46db-a85b-e38fc5600988/can_you_use_xbox_one_turtle_beach_on_ps4.pdfIn PDF document text
    • https://03aaa7dd-6608-466c-a68c-f41c59811c05.filesusr.com/ugd/ae15ca_5e1179b5b69440a28f971cac2bcfba6c.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f036.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF036 5328 bytes
SHA-256: 51ca81154615f363fe1b7335779135b1c7a3a25d41061f1f8ce1bf83545fc660
font_01_sfnt_off0001023c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1023C 10788 bytes
SHA-256: 289f83b8f426b962190b3dd3d670edd40f0c862fa9357f3869aa9a58f78a9bae
font_02_sfnt_off0001271a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1271A 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333