Malicious PDF — malware analysis report

Static analysis result for SHA-256 f9451f20c0e6646e…

MALICIOUS

PDF

96.0 KB Created: 2021-05-25 04:47:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c370c1a1e12ec33dffa79a601ea664ce SHA-1: 7720a6ceb7b87fa4a1bd96fde3e467a17e5bacef SHA-256: f9451f20c0e6646e6df36b5f91283c96ceaa24f9e6483ee0d0ba3db8cf380656
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to potentially malicious domains, suggesting a link farm or phishing attempt. The heuristic PDF_SEO_LINK_FARM indicates a mass of external PDF links, and the ML classifier and ClamAV detection strongly suggest malicious intent. The primary malicious URL identified is https://nipisod.ru/strik?utm_term=the+legend+of+korra+turf+wars+portugues+pdf.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://nipisod.ru/strik?utm_term=the+legend+of+korra+turf+wars+portugues+pdf
    • https://static.s123-cdn-static.com/uploads/4421330/normal_5ff2da1c4774b.pdf
    • https://cdn-cms.f-static.net/uploads/4470981/normal_605d42250c97f.pdf
    • https://pirizujimo.weebly.com/uploads/1/3/4/4/134454944/kukemozofemeluxuwu.pdf
    • https://savapavazatu.weebly.com/uploads/1/3/4/6/134677348/bijomenamaxi.pdf
    • https://static.s123-cdn-static.com/uploads/4465539/normal_5fe2dbe48a72a.pdf
    • https://bojufare.weebly.com/uploads/1/3/1/0/131070992/papufuvufigu_monuzaboso.pdf
    • https://static.s123-cdn-static.com/uploads/4502248/normal_5fcd5dc67d4e6.pdf
    • https://cdn-cms.f-static.net/uploads/4389792/normal_604d34016d79c.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/c191c6ed-6bb4-4422-ab5f-672a46b6b8c0/66828062628.pdf
    • https://uploads.strikinglycdn.com/files/c64f68d6-4a14-4925-8150-13592d5685c9/kawotewodel.pdf
    • https://uploads.strikinglycdn.com/files/6696861e-5571-4533-95d2-fa4877c3b88a/is_one_touch_ultra_mini_discontinued.pdf
    • https://uploads.strikinglycdn.com/files/49623f9d-e541-4d65-b569-92d9f77a7826/troy_bilt_tiller_serial_number_list.pdf
    • https://uploads.strikinglycdn.com/files/dc4a2d69-c46c-4830-b5dd-37baf36782b9/tilegowupomofapulukas.pdf
    • https://uploads.strikinglycdn.com/files/6330185b-69e8-40fc-a70b-1c812f2f707a/dogiguzud.pdf
    • https://uploads.strikinglycdn.com/files/45d51b5d-21f8-464d-bea6-46c78ffef30c/73555059885.pdf
    • https://s3.amazonaws.com/lixisariwulo/furoje.pdf
    • https://uploads.strikinglycdn.com/files/1b682e9c-296a-4b8b-80d7-3e6405d1048a/the_48_laws_of_power_robert_greene_review.pdf
    • https://uploads.strikinglycdn.com/files/35032b0c-91c8-49cf-8bcf-960391ec0ae5/7_day_flat_belly_tea_cleanse.pdf
    • https://s3.amazonaws.com/piwupevivotixi/tratamiento_para_cetoacidosis_diabetica.pdf
    • https://uploads.strikinglycdn.com/files/e2cf90ab-5323-4713-935f-c89f46349879/american_society_of_plastic_surgeons_2016_plastic_surgery_statistics_report.pdf
    • https://s3.amazonaws.com/wolawatin/does_all_fibre_cement_sheeting_contain_asbestos.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001356b.bin
0314ceb740b497b8c73d57e0f634187e62bb29d98d4c6b455c1a333c672b0b6d
pdf-font-stream PDF embedded font (sfnt) at offset 0x1356B 5408 bytes
font_01_sfnt_off000147e0.bin
af53e68ef941c225615523cc3f77e427fc4582b109c9ae2a4b135b95e84f14ae
pdf-font-stream PDF embedded font (sfnt) at offset 0x147E0 13068 bytes