Malicious PDF — malware analysis report

Static analysis result for SHA-256 f631e78ec8b4c579…

MALICIOUS

PDF

90.7 KB Created: 2021-04-12 15:56:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-16
MD5: 1e2f524f8c6501f260dc2d971e2d4e88 SHA-1: 24b7f58bd78055b441576fbd69c0bc6126d1c175 SHA-256: f631e78ec8b4c579792e51f41aec264df249d79b6279e99e76cde7c7872e2f32
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, with a significant portion pointing to disposable hosting and exhibiting link farm characteristics. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of external URIs and the link farm heuristic suggest an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://crophysi.ru/strik?utm_term=how+to+copyright+symbol+on+mac PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4406456/normal_5fe467b8e3651.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4464710/normal_5fed98c5061bf.pdfIn PDF document text
    • http://coolvdomaion.online/92939624902mh238.pdfIn PDF document text
    • https://cdn.sqhk.co/pixorikibam/rntiaIr/razipekedatetitusowaluv.pdfIn PDF document text
    • https://cdn.sqhk.co/zuvutose/SCijhiU/flood_report_in_river_chenab_today.pdfIn PDF document text
    • http://lovechat24.club/pit_bike_racing_parts6r1rm.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4366045/normal_6011bea121beb.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4462038/normal_604ad6fd7677a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4390092/normal_6026bfcd64afd.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4459175/normal_5fe0461c6282f.pdfIn PDF document text
    • https://cdn.sqhk.co/feduvefas/dp3gdYP/nuxikalaw.pdfIn PDF document text
    • http://carinsusa.info/spectrum_math_workbook_grade_8_free92cvz.pdfIn PDF document text
    • https://cdn.sqhk.co/gelowidabik/eieijwn/lelapamumumolivedisebo.pdfIn PDF document text
    • https://cdn.sqhk.co/falupuvevore/ibjigj1/90946605199.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4392864/normal_60114b8b6633c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4424364/normal_6035487d7306a.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4420903/normal_5feaf9591adce.pdfIn PDF document text
    • http://www.typoland.com/http://www.typoland.com/designers/Lukasz_Dziedzic/CopyrightIn PDF document text
    • http://www.typoland.com/In PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://pikegasek.epizy.com/is_there_gonna_be_warcraft_2.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/89d0739e-998b-4432-ae4f-ca0fd09fafd1/georges_secret_key_to_the_universe_series.pdfIn PDF document text
    • http://tojetejuru.rf.gd/skewness_in_statistics.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cba02d19-d3be-4cbb-a327-e6eecdcbd762/fifaxoremitapafuziso.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/40bd892c-15b0-481a-9203-010c473cf227/baxuvivog.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/35ba6057-4990-4393-97a9-60742f2d95cd/a_time_to_kill_movie_free_online.pdfIn PDF document text
    • http://punegejofuj.epizy.com/lobusitogudulilovemumet.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000105ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105AB 3068 bytes
SHA-256: 4a874eb1ba5c87732194c9a2b17b9f02cff39e82ccd3a2a7670b627809885069
font_01_sfnt_off00011060.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11060 6168 bytes
SHA-256: 0e87cd05f332aeb2a72b3daf131c0310eff8a4a40b86507956a7cca2f5d1d305
font_02_sfnt_off00012002.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12002 5644 bytes
SHA-256: 32ce062aabab8c98c001ee0ad1c922686c8b21472971b898a29574b4a669a592
font_03_sfnt_off00013321.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13321 12396 bytes
SHA-256: b094405fc62fb88df4d6cdb2684f50b93e80de986664c00d4017f1875ee99438