Malicious PDF — malware analysis report

Static analysis result for SHA-256 38cb99be4af694f1…

MALICIOUS

PDF

95.6 KB Created: 2021-03-14 06:00:31 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: fae9c37d7dec8e43b6402dcffaa60c04 SHA-1: 11e0474a6a417d3f4eefab7459aa66d79bc1bfaf SHA-256: 38cb99be4af694f11ae42a73f3acbb68a4da7de865ed065bb7086b890b041677
126 Risk Score

Malware Insights

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

This PDF document contains a large number of external links, many of which point to disposable hosting services and utilize UTM parameters, indicating a link farm or SEO manipulation tactic. The ML classifier strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the PDF structure and extensive URL usage suggest it's designed to redirect users to potentially harmful content or facilitate further malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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.
  • 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://leonvi.ru/123?utm_term=filemaker+pro+6 PDF link annotation
    • https://cdn.sqhk.co/foropogajag/h7uRjei/95050471996.pdfIn PDF document text
    • https://cdn.sqhk.co/xakutofi/0gc5hiN/reversi_glow_new_reversi_game_free_online.pdfIn PDF document text
    • https://niregesop.weebly.com/uploads/1/3/0/7/130776037/3410808.pdfIn PDF document text
    • https://cdn.sqhk.co/simikitivo/imgfEvm/jurassic_world_the_game_cenozoic_hybrids.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384048/normal_601a1c9e32a29.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4484993/normal_5fd088ba5bc20.pdfIn PDF document text
    • https://cdn.sqhk.co/xubipoxeguza/gchK9TQ/defasofajogidivoke.pdfIn PDF document text
    • https://cdn.sqhk.co/modesarox/fjaf0jh/32522992557.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4427287/normal_5fe4b9c6dcfe7.pdfIn PDF document text
    • https://lidaleteso.weebly.com/uploads/1/3/4/0/134017218/rosudazap.pdfIn PDF document text
    • https://bojuwidus.weebly.com/uploads/1/3/4/6/134698781/7974356.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4491665/normal_5fd95fbb83b58.pdfIn PDF document text
    • https://turugoduzo.weebly.com/uploads/1/3/0/7/130739986/15eee264a5a.pdfIn PDF document text
    • https://cdn.sqhk.co/zozijawutuxu/jgicGie/silaxodafitaxobozu.pdfIn PDF document text
    • https://cdn.sqhk.co/gopepilexafi/Rhdxgf4/unlimited_free_vpn_betternet.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/b409b988-dea6-4b98-b5de-a485e189e999/18808453611.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/47f81185-0bd1-4fb9-848a-69c850e73ecd/black_and_decker_hedge_hog_edger_replacement_blades.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cc5b1e7c-5984-4a29-b5cc-9239e8398354/7385835717.pdfIn PDF document text
    • https://s3.amazonaws.com/rujabepifar/mixed_up_files_of_mrs_basil_e_frankweiler_summary.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/34964f13-dfa7-4409-b5a9-ac1088d95f4e/wepanurubewomas.pdfIn PDF document text
    • https://s3.amazonaws.com/tipikaxe/uso_de_antiarritmicos.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012b02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B02 4560 bytes
SHA-256: 39b6568c841d3d13783898a366a9d0111294f6bd1808535612e53b9918e73042
font_01_sfnt_off00013a6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A6F 12136 bytes
SHA-256: 44e20fb8145e49fe7980d30ead87f7cfff251b620cc5a7da816874fee0640bc5
font_02_sfnt_off0001620d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1620D 4324 bytes
SHA-256: ff5f0ef16caf3e97cd1984b3a03ea88e11eab8cf63d2ee006085a4b9995833f3