Malicious PDF — malware analysis report

Static analysis result for SHA-256 28c47c76443386ec…

MALICIOUS

PDF

112.2 KB Created: 2021-03-30 20:01:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: 412f538749358bc891ccffc5dc9208e1 SHA-1: 1cce938dc3051741062347fefc2b8bd48427c5e0 SHA-256: 28c47c76443386ec43a3540c0af8360f96c7458eef0eeaeb7c3f4949a5cad3e6
186 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or SEO manipulation scheme. The primary URL, https://nipisod.ru/award?keyword=apertura+a+la+experiencia+pdf, is likely part of this malicious infrastructure. No scripts were extracted, but the PDF structure itself is designed to redirect users to potentially harmful external content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://nipisod.ru/award?keyword=apertura+a+la+experiencia+pdf PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4479707/normal_60580baaa5ab0.pdfIn PDF document text
    • https://rapagifetudi.weebly.com/uploads/1/3/2/6/132682686/3398461.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481278/normal_601595d62493c.pdfIn PDF document text
    • http://siwikilapezufi.iblogger.org/kajutatoxudupofak.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4402294/normal_605887160123a.pdfIn PDF document text
    • http://tolumobibuseg.iblogger.org/almasry_alyoum.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4407749/normal_600728c210fdb.pdfIn PDF document text
    • https://veluzikekador.weebly.com/uploads/1/3/4/8/134865338/faff2eeba72533c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4493888/normal_5fd36ac0d3e17.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/99ece0a1-d510-4b0b-8a0f-20d0d5e9140e/28800436497.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/910a8414-04b6-408c-a234-2b0eed701765/dakixunexoridamu.pdfIn PDF document text
    • https://s3.amazonaws.com/wesezuzuvalirik/icc_guide_to_incoterms_2000.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a0377994-66a0-43f4-9fca-b9e6505ed520/2005_jeep_grand_cherokee_4wd_not_working.pdfIn PDF document text
    • https://s3.amazonaws.com/bulolimepol/agendas_for_meetings_templates.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0474b214-5267-4f2c-a0e5-fb2238ff0d7c/how_to_teach_wrestling_basics.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/42d1857d-6b7d-4a2e-922a-0eb07671bc92/solid_state_physics_pillai_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3db64de9-4027-4931-8c5a-1d5143d1c838/56682963048.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a654b9db-c877-4377-8387-e49c19e579d8/63831586136.pdfIn PDF document text
    • https://s3.amazonaws.com/tugafebip/5322188627.pdfIn PDF document text
    • https://s3.amazonaws.com/jukoxisojow/us_portal_docket_sheets_pa.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000162c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x162C6 5028 bytes
SHA-256: e8edc25aacc5a46ca31b2db16fa987a28a5f8cec6f41e3844a70d8e77e587842
font_01_sfnt_off000173f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x173F5 12528 bytes
SHA-256: 4dd443139ca32f7f078545726af15db87467103cf563e0444c9c5a5cd4b37283
font_02_sfnt_off00019c9a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19C9A 16060 bytes
SHA-256: 5b0d2701ab39d2f69c66d7d16c60d8db0b323aa0832947137e757b5401d27330