Malicious PDF — malware analysis report

Static analysis result for SHA-256 5f31550f09f45a93…

MALICIOUS

PDF

78.7 KB Created: 2021-03-25 02:52:02 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 529aeb7ea9d124ce67eb7071779f5d34 SHA-1: 7ee95f0e0583e9a64b5ad464b2a01f2bcc1d49e0 SHA-256: 5f31550f09f45a938f52324b9408312d13e1444e0b0f91f9ff09aeb9579d6f86
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 hosted on disposable domains, indicating a link farm or SEO spam campaign. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards a malicious document designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://baarspo.ru/strik?utm_term=what+is+working+memory+capacity+in+psychology PDF link annotation
    • https://perasukene.weebly.com/uploads/1/3/4/6/134644841/756e45b39d29.pdfIn PDF document text
    • https://nozabuzewetuk.weebly.com/uploads/1/3/2/6/132683147/2f58880a1938.pdfIn PDF document text
    • http://wepalulinoviwo.iblogger.org/wimipigulunu.pdfIn PDF document text
    • https://lulotabo.weebly.com/uploads/1/3/4/7/134745182/87229b2ac9.pdfIn PDF document text
    • https://kimuremosov.weebly.com/uploads/1/3/4/7/134732255/3677512.pdfIn PDF document text
    • https://bukodagunotul.weebly.com/uploads/1/3/4/0/134012399/4750892.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://tirujukixiw.epizy.com/sample_appraisee_comments_for_performance_appraisal.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bf2f57c2-b915-43aa-9e1d-f3c053bbe15b/10081896150.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7f6a07fe-8c26-4454-9f65-2224310a0ec2/mercury_150_efi_for_sale.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3ee45cd8-dfbe-4a5a-824e-4cee1fb43ef7/lord_of_the_flies_chapter_1_reading_and_study_guide_answers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3b322090-9a5e-47e0-ae6d-3437e190d77b/did_u_get_it_spanish_worksheet_answers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0d692220-8d8b-4584-af1d-6db55d0b1d36/xukuwuxus.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8f25ec9b-d4ee-4dac-a5fd-a1d019c1775f/harry_potter_and_the_goblet_of_fire_movie_plot.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4f17e467-7626-4152-b2b3-78fa63c5d6d6/80951662844.pdfIn PDF document text
    • http://galopaxuvubopuj.rf.gd/will_a_hermie_produce_buds.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3459f5cf-c32b-4eba-aaac-dcabba8ae88c/12839960666.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5ed5a5d7-709d-493e-af65-66f9599f29fe/66262249918.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/48c59976-9d9e-4ce7-9a4d-4586fc58b76f/graco_duet_sway_lx_swing_with_portable_bouncer_instructions.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/30d14c90-5fdf-4105-a616-2798e75b0232/can_you_trade_forex_with_1000_dollars.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/707f4462-fc07-4079-a071-2af72798e4b9/84439145821.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0990036b-9b23-478b-8b97-9853b16812d8/beginner_python_projects_github.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_off0000f4fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4FC 5620 bytes
SHA-256: deccec0e42610dd0fa985f12d1929d4d1d61911dde06e6b51701658ab8aad247
font_01_sfnt_off0001080c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1080C 11008 bytes
SHA-256: 61558f82e33097faabe146490da1fa2a140a2bbff3b37dbe3b40c1fc3603d774