Malicious PDF — malware analysis report

Static analysis result for SHA-256 3921caf9f50c55f7…

MALICIOUS

PDF

108.9 KB Created: 2021-06-09 05:53:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 5bc7ccc529b69b66ebfcecb0fad0fddd SHA-1: 66cafb25737d429d440efb8426f932c2c9378c62 SHA-256: 3921caf9f50c55f760d8a72f6b9ffe913373d856c695a6421b370fc605015cda
186 Risk Score

Malware Insights

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

This PDF document is identified as malicious by multiple heuristics and a machine learning classifier, with ClamAV detecting it as a phishing trojan. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or SEO spam operation. The embedded URLs are likely used to redirect users to malicious sites, potentially for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://huntic.ru/pbw?utm_term=bioelectricity+a+quantitative+approach+solution+manual PDF link annotation
    • https://sekojufakov.weebly.com/uploads/1/3/0/7/130776719/3139999.pdfIn PDF document text
    • https://nirawulef.weebly.com/uploads/1/3/4/3/134324477/wujupakesu_pujusaperalubi_gujuv_potosan.pdfIn PDF document text
    • https://wuzipagaxu.weebly.com/uploads/1/3/0/7/130776492/13eacea3d2.pdfIn PDF document text
    • https://gazoxawirola.weebly.com/uploads/1/3/4/5/134588870/7499298f630f.pdfIn PDF document text
    • https://genodekavukip.weebly.com/uploads/1/3/1/6/131607477/7792737.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/02c13c75-485e-4dac-8d27-33c5600c60e0/tibemosate.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cd71b6a5-91aa-4bf1-97e2-a07b75766156/gns_430_installation_cost.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c22876a7-2daa-4c2d-90f8-b52193eac1fc/american_red_cross_online_first_aid_renewal.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b4cbd0b8-1b64-4c28-af71-112f3a7eface/87017238602.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f7edd658-0062-4fbb-8451-7c33d1fc3d78/what_is_cottage_food_law_california.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3874187b-1ed4-48b3-a6d9-7f092c9c7da2/list_of_functional_training_exercises.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4c5b34b8-2a80-4a3d-bf3a-ad5fc587110b/48894514134.pdfIn PDF document text
    • http://vojewukejiwu.pbworks.com/f/driver_booster_7.1_pro_key_free.pdfIn PDF document text
    • http://gokewisu.pbworks.com/w/file/fetch/144739032/wutotonoxutitomeroposo.pdfIn PDF document text
    • http://mukonisu.pbworks.com/f/oraciones_subordinadas_adverbiales_causales_resueltas.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/50518b4a-ac66-40c3-b44a-2ce6396b2fd2/how_to_program_rca_universal_remote_to_vizio_sound_bar.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5a49f8bd-53f2-4cff-b143-6558064a550f/get_codes_check_engine_light.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/53552b80-286a-4480-a7d1-fc3896353d07/2000_jeep_grand_cherokee_laredo_engine_swap.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_off00016967.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16967 5508 bytes
SHA-256: 7bfc7d0e855f43a1ad8a739874a2dee2292eec45a7e5be2f1abf84af47857ae4
font_01_sfnt_off00017c11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17C11 12100 bytes
SHA-256: e8f547c6ac68b984b42c993866e4efdcc962f44cf0c017975b54bd1dbd1d3d5e