Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf81545460888597…

MALICIOUS

PDF

75.2 KB Created: 2021-02-18 12:39:04 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: bfdb6c171ce932982d769b3a48396616 SHA-1: 60c740c7bbec0b8ef5acdd2926b0f9cd359cc503 SHA-256: cf81545460888597cc8e26e850f61cb7220836ff524ad60fe4685e5423ba651b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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 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/123?utm_term=are+bostitch+air+compressors+any+good PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4448337/normal_602171248d6eb.pdfIn PDF document text
    • https://jajesawi.weebly.com/uploads/1/3/0/8/130813829/4466938.pdfIn PDF document text
    • http://shopsmmv.site/graco_snugride_click_connect_35_car_seat_installationvbf7u.pdfIn PDF document text
    • https://muwegegedagus.weebly.com/uploads/1/3/0/7/130738526/3873776.pdfIn PDF document text
    • http://grizhoff.ru/cisco_anyconnect_profile_editor_4._64wa1y.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367921/normal_602191bf5f7cf.pdfIn PDF document text
    • http://mists.space/tozila5zc7t.pdfIn PDF document text
    • https://cdn.sqhk.co/vazoguzo/PighcO1/99152030635.pdfIn PDF document text
    • http://shlifovka-pol.website/nanda_2015-2017_downloadzob2d.pdfIn PDF document text
    • http://50off.pro/ballade_pour_adeline_original_piano_sheetabh9e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4407576/normal_601b1890759d9.pdfIn PDF document text
    • http://hdvideo.design/gepofudunuzetozawxcww.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/regegozumekoza/photo_bokeh_app_for_android.pdfIn PDF document text
    • https://s3.amazonaws.com/xamibudasagas/9274062146.pdfIn PDF document text
    • https://s3.amazonaws.com/lolijexejomak/earthquake_epicenter_lab_answers.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_off0000e826.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE826 5684 bytes
SHA-256: ba9ec657a23b349b167a39ab6519a5c8dcb904c730ac4bb33d7a6c1f61cdcdcb
font_01_sfnt_off0000fb55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB55 10776 bytes
SHA-256: 1e43199767e0d997cdfe136d5cdb31cca966f433d69985aa1116ba9bd620e993