Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3c51ea2347e897a…

MALICIOUS

PDF

76.5 KB Created: 2021-03-08 21:59:59 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 7212d52032100baa90808c1e5cebe02c SHA-1: f55be61bdcf1ffaa39b03b0e273fc02733dcb45a SHA-256: c3c51ea2347e897ac800bf27e1fa4dd4c2056c5406c2674842e1e7106351267d
186 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was identified as malicious by both a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, embedding numerous external URLs, with a primary URL pointing to zajinet.ru. This suggests the document's purpose is to redirect users to potentially harmful or deceptive websites, likely for SEO manipulation or phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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=engineering+reports+references PDF link annotation
    • https://cdn.sqhk.co/jigixomavola/egdhg7Y/65518160053.pdfIn PDF document text
    • https://kakituku.weebly.com/uploads/1/3/4/5/134589995/3152451.pdfIn PDF document text
    • https://pugotaba.weebly.com/uploads/1/3/5/3/135302821/35ac0e242da.pdfIn PDF document text
    • https://xolopebowuraj.weebly.com/uploads/1/3/4/6/134600193/1150834.pdfIn PDF document text
    • http://about-fb-support.com/damulorojudekemofavuxubo3psmo.pdfIn PDF document text
    • https://dufofisejufosu.weebly.com/uploads/1/3/4/8/134875198/nuparexovijinuz-gonom-koxiwulamolujo.pdfIn PDF document text
    • http://trokot-shtorki.online/latesozatoeu6m1.pdfIn PDF document text
    • https://gonadavosipew.weebly.com/uploads/1/3/4/5/134595915/bopoxupuxulomoxe.pdfIn PDF document text
    • https://cdn.sqhk.co/taxeseta/OIChcYO/lebawomozejunevozufam.pdfIn PDF document text
    • https://cdn.sqhk.co/wolanojijen/fjgjjEr/sewedesod.pdfIn PDF document text
    • https://tetuxexe.weebly.com/uploads/1/3/1/8/131871535/9864097.pdfIn PDF document text
    • https://cdn.sqhk.co/fomeluxilim/iigPiiT/tickled_pink_seymour_ct.pdfIn PDF document text
    • http://raicen.com/pixerireneslq12.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/e96381c4-9fa1-4d1e-8bc3-07f66a961255/the_husbands_secret_plot_spoilers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8623eb33-ddcd-420d-bd1e-73ebbc9e25a3/does_ikea_sell_replacement_screws.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0bc07759-5e05-465f-8b4a-c9784b00df0f/how_to_use_sentence_structure.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/530dfdec-bd05-481e-b553-b3664f99ba3a/how_much_is_paige_worth.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3c4fd50a-7039-4cc6-8ece-b39c878e8174/puxogopoburadijizo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/72b28bb5-b705-4165-ad41-ba051035d1d5/2008_nissan_sentra_service_engine_soon_light.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d9ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9BA 4900 bytes
SHA-256: 9df375c5db20d306337f53405f44c9a7bf5eced275b97e7738e120a564397649
font_01_sfnt_off0000ea8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA8A 10760 bytes
SHA-256: 890208dac31a1f0aea3e78ea7d7aec221eb5cea4c35d0a8f51d36db2ebd34bdc
font_02_sfnt_off00010f72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F72 16144 bytes
SHA-256: 18f56b7fae04e07bc119a468ad323bdda099da77b0772854d1c47cc1f39b9f3b