Malicious PDF — malware analysis report

Static analysis result for SHA-256 55ab1498ca3aa85d…

MALICIOUS

PDF

71.3 KB Created: 2021-04-03 05:04:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 9b23d0f9f222a6330ccafb4ab46e6608 SHA-1: f2af0cf2fa3d63276e71f3f948acf341bc95d367 SHA-256: 55ab1498ca3aa85d948a20003f63c3b217f80d6cb3b170abae3b2ae8807bcd4a
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://kuzutuzo.ru/wix?keyword=bissell+proheat+2x+premier+pet+instructions PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4412762/normal_5ff24be158dfd.pdfIn PDF document text
    • http://magic-spring.com/genarsiyrp.pdfIn PDF document text
    • http://bet-info.ru/pc1832_reset_master_code9hluy.pdfIn PDF document text
    • http://taher-tcac.com/how_to_activate_dell_active_pen_pn350mwbkoy.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474231/normal_5fda8e03789a4.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4413362/normal_60079801d4090.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4466673/normal_5fcf16e1cdb74.pdfIn PDF document text
    • https://cdn.sqhk.co/bajilevone/0Dmhbij/tamilrockers_movie_app_for_pc.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453344/normal_6041d359d3329.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384307/normal_6049212ae114c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4425492/normal_6063eda08b4f0.pdfIn PDF document text
    • https://cdn.sqhk.co/gotakavapu/gh2jhhj/nissan_connect_ev_app_review.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422628/normal_6057ba74f0aa5.pdfIn PDF document text
    • http://cookwellbakewell.com/milelififepuxofax8bdqz.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/rozebofukixus/augmentin_suspension_dosage_forms.pdfIn PDF document text
    • https://s3.amazonaws.com/najipavez/lonewajorakafuwoli.pdfIn PDF document text
    • https://s3.amazonaws.com/satulibaren/laxuzafeniluz.pdfIn PDF document text
    • https://s3.amazonaws.com/kitakilesa/wojozozadajetawosagasavi.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_off0000da64.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA64 5424 bytes
SHA-256: 9a99e48da2bb7979ee3aa20e45f134e280ec9efaa972d30c157f5f5699552c97
font_01_sfnt_off0000ecb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECB1 10280 bytes
SHA-256: 9d6cc04f9de12cc5541f1f3dea084b0a9f55f1c848404d6aba3091fb42b6834c