Malicious PDF — malware analysis report

Static analysis result for SHA-256 28f3fc9c53d8613b…

MALICIOUS

PDF

81.4 KB Created: 2021-03-05 07:41:19 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: 8e1b619d4c402e40936bd4757a2a3af2 SHA-1: 9449e362d033cff0156c1b0efdf081d517ed8906 SHA-256: 28f3fc9c53d8613b6a69b3cb61e417c0dfa5f69c2b459504d19ef993a7ad2a42
186 Risk Score

Malware Insights

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

The file is a PDF containing numerous embedded URLs, many of which point to disposable domains and are likely part of a link farm or phishing campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of embedded JavaScript, though not explicitly detailed in the provided evidence, is a common vector for malicious PDFs to execute actions or redirect users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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
  • 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://zajinet.ru/123?utm_term=how+to+get+100+rdr2 PDF link annotation
    • http://politach.com/28986434230zn81i.pdfIn PDF document text
    • http://glasshookahcatering.com/huawei_airtel_4g_hotspot_appwrp2t.pdfIn PDF document text
    • http://autobuff.xyz/35721397796e5dym.pdfIn PDF document text
    • http://namedaun.fun/eogifee_35t_ceiling_fan_remote_control_replacement_of_harbor_breeze_kujce9603_fan35tx6ktj.pdfIn PDF document text
    • http://localdesign.me/juegos_de_pelea_el_hombre_araa5zvdj.pdfIn PDF document text
    • http://fringigejy.site/pevelirunutafavubaszpb9h.pdfIn PDF document text
    • http://hopecommunitynaz.com/98181130615mnquy.pdfIn PDF document text
    • http://pokupka.space/sevudurutawojuzag9996f.pdfIn PDF document text
    • http://organic-ita.space/jobisakumizexivimumm0z6.pdfIn PDF document text
    • http://natfreshik.fun/tepur8ri5s.pdfIn PDF document text
    • http://wwwbcpzonasegura-viabcp.com/don_t_starve_shipwrecked_best_recipes2xea3.pdfIn PDF document text
    • http://leoidet.xyz/13867658922y1c1.pdfIn PDF document text
    • http://dkmz2.club/kevudodinutupofe8s.pdfIn PDF document text
    • http://invitesistem.ru/81361773578lvki0.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/8f87f737-0c1b-416b-9628-7a7a11d9d228/weather_map_worksheets_6th_grade.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4133176b-035f-4b4b-be70-8fd85f5545e4/venta_de_monitores_de_signos_vitales_usados.pdfIn PDF document text
    • https://5ccda086-29c7-4024-8a93-689df1f3b89c.filesusr.com/ugd/ed8107_a56d7e7908bb4699a69db7f4f1686961.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/5e06a504-10b2-4e55-a07f-f89f2b3927ad/phonological_awareness_skills_test.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bb737b5b-f955-432c-bd71-ddaf11165983/sony_pxw-fs5_specs.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7db66c65-6173-4c06-8d7a-cabc712d78ae/60133110160.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bdfc8026-1f25-4d87-9794-c3ab214c4f35/tujoxegomulek.pdfIn PDF document text
    • https://8569cc17-8b2a-4187-ace0-95b0550b99f0.filesusr.com/ugd/d6eede_e5a53d210ae849f883f7eb4e64b9c788.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c750317b-0cc7-44a0-8228-c776f73f7a5c/jinax.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2029dd14-458b-4321-8595-3ee705ed92db/philips_simplygo_portable_concentrator.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_off0001020f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1020F 4952 bytes
SHA-256: b1bb3676e051c59edfacb172adeb1835562d0e3e9cc0dc96cc394c953fe74f39
font_01_sfnt_off00011315.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11315 11104 bytes
SHA-256: 13a8d373ee463ed59f5b35e89908b3a34a082c038e503c1b8b1404220b55296c