Malicious PDF — malware analysis report

Static analysis result for SHA-256 94686f627f168686…

MALICIOUS

PDF

73.4 KB Created: 2021-06-14 08:55:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 9977d56d0087e53ad7e34e787ffb0b28 SHA-1: e86a31e013c1444ada6bddeba6c8625224348f36 SHA-256: 94686f627f1686860a98b0ba425ef708732a09b9f09efce163dc03b7ae8638ba
186 Risk Score

Malware Insights

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

This PDF file is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to numerous external PDF files, with the primary lure being "Integrated chinese workbook 1 answers". The PDF contains multiple external URIs, suggesting an attempt to distribute or redirect users to other malicious or spam content. No scripts were extracted, but the structure and URL patterns are indicative of a phishing or SEO spam campaign.

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://drafthe.ru/pbw?utm_term=integrated+chinese+workbook+1+answers PDF link annotation
    • https://kiruxujekan.weebly.com/uploads/1/3/2/7/132740547/fotave_wevojakodobisu.pdfIn PDF document text
    • https://jijavizoj.weebly.com/uploads/1/3/4/5/134582380/848bfc22a1b2f.pdfIn PDF document text
    • https://pigodebi.weebly.com/uploads/1/3/4/8/134864190/234868b.pdfIn PDF document text
    • https://javowutimor.weebly.com/uploads/1/3/4/0/134016661/lexovow.pdfIn PDF document text
    • https://merotulup.weebly.com/uploads/1/3/4/0/134000288/7451590.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/369de900-ae5e-4d55-bd10-c5e2a4bc9e4f/cross_over_to_the_other_side_definition.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0d4754e0-79fa-41a8-8166-f3ce3f2b7a7a/9319630995.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d4586545-6d2b-461c-941e-d6df6c0653b7/the_veldt_by_ray_bradbury_video.pdfIn PDF document text
    • http://zuguwar.pbworks.com/w/file/fetch/144728268/jonathan_livingston_seagull_multiple_choice_questions.pdfIn PDF document text
    • http://mituxap.pbworks.com/f/bol_do_na_zara_female_ringtone.pdfIn PDF document text
    • http://rulemujog.pbworks.com/f/15321414071.pdfIn PDF document text
    • http://bikopatepo.pbworks.com/f/fitonale.pdfIn PDF document text
    • http://sozegajamuf.pbworks.com/f/zowajuvoku.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6840c44d-3f5d-441a-8e0d-0b33cb787ebe/how_to_operate_mazda_remote_start_compustar.pdfIn PDF document text
    • http://zotugon.pbworks.com/f/adjustment_disorder_with_depressed_mood_dsm_criteria.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/627932e3-5c26-4bcf-9946-83eaf23ca8d6/microsoft_word_cv_templates_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0c59070b-c6e0-4f3b-be0d-3cce5565c714/betigu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8900ddd0-7773-4bcb-8619-b1e0857427e1/data_security_policy_template.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/755e4abf-5417-4037-9344-0cbf523871b0/kedigodaruwazemarepuxo.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c367.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC367 3276 bytes
SHA-256: ea56af53611d7a20865f992dad340f36d42adf487415085bdcc75513b87b5f43
font_01_sfnt_off0000cf35.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF35 5452 bytes
SHA-256: 9041b58480f64318e7edf08287d431ea214b9376dd22b8c301d03d23e88fc93c
font_02_sfnt_off0000e1d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1D3 10268 bytes
SHA-256: 66a5d7a0f165ac7af855bffe223c197d1059c7a14e9ac4b771f3bb8deed4fca1
font_03_sfnt_off00010315.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10315 16060 bytes
SHA-256: d8a1a34de14a7b8fce5e51635835121d353d188f9ac9ce1e11538509fd4c5cdc