Malicious PDF — malware analysis report

Static analysis result for SHA-256 4156d8b71a9ad1da…

MALICIOUS

PDF

74.8 KB Created: 2021-03-17 02:27:56 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: e59470e40e00c71c0b01e0945f897688 SHA-1: 564adbf4afd6d8a9411d4a9e8b7fd24d405e77a6 SHA-256: 4156d8b71a9ad1da223e3737811736ab7835a7ffbe4e6acceab519e14ee937eb
166 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 0.9993

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Image-heavy PDF with invisible link to suspicious domain high PDF_SUSPICIOUS_LINK_LURE
    PDF is a small image-heavy lure with invisible link annotations that send the user to a suspicious high-risk-domain URI. This matches credential-phishing carriers where the visible document is only a prompt and the real collection flow happens on the linked website.
  • 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://jottigo.ru/strik?utm_term=how+to+read+rheem+water+heater+model+numbers PDF link annotation
    • http://damomemisogadex.iblogger.org/lawerudisurok.pdfIn PDF document text
    • http://molotkov.site/vejikefenuwajish39r.pdfIn PDF document text
    • http://afracheat3.xyz/zomujakufebezugeluvasohwxdn.pdfIn PDF document text
    • http://micrometer25bill.site/david_harvey_the_right_to_the_city_summaryqs23p.pdfIn PDF document text
    • http://tonagruz.ru/vaxolotejugxezx.pdfIn PDF document text
    • http://securitycheckingbrowservkcom.xyz/honda_gcv160_mower_spark_plugd0qka.pdfIn PDF document text
    • http://kefets.xyz/el_libro_de_los_abrazos_fragmentos4t63r.pdfIn PDF document text
    • http://lnstagram-blue-ticks.com/fufegumuzed868qe.pdfIn PDF document text
    • http://matras-24.ru/11450795403ro5a8.pdfIn PDF document text
    • http://xusolupofedowi.iblogger.org/cutting_edge_elementary_audio_cd_free.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://vevugep.epizy.com/69021550233.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/181198a6-32a2-43ce-acfb-0bbba62e602b/64460554756.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/77b2c125-70b1-46c7-a4c0-99b054ca4e95/lenovo_g50-80_laptop.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/71249517-a35c-4bff-9aab-200cae8e8b36/the_summoning_book_trailer.pdfIn PDF document text
    • https://s3.amazonaws.com/didowugorokirug/nefulesedik.pdfIn PDF document text
    • https://s3.amazonaws.com/mejifavo/nubuligubaligakuxitopu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d9dd067f-8c30-4e8f-abfa-0353fd9715fa/ncert_english_grammar_book_class_6.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5baba41a-3d92-4377-8062-7bd9b306f4f5/lyman_reloading_data_30-06.pdfIn PDF document text
    • https://s3.amazonaws.com/bededuxotulapil/la_cicala_e_la_formica_poesia.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f98af142-1f31-45b3-9087-3c8219bdafcf/79846911170.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f8d8f8e3-b08f-43b2-a0d4-eb3d2f42af3c/30327526178.pdfIn PDF document text
    • https://s3.amazonaws.com/lorifumofelu/sample_performance_appraisal_report.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7e79f646-6dd8-40a0-bb5e-99f8181ad65a/tewunopisaxulejukutof.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_off0000e5bb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5BB 5256 bytes
SHA-256: fabe1f487b645137d092e6fe879f6781b89ce81523b5ad1cebce159c81e4343a
font_01_sfnt_off0000f775.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF775 11300 bytes
SHA-256: 62fbc148f9ec0139ecaa7337fc5f8a5401dece8dee258c896136a56ea3026dbc