Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ff206fd8c3076c8…

MALICIOUS

PDF

70.9 KB Created: 2021-03-16 21:50:35 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 926129918b3a64cd630a095ffd0736f0 SHA-1: c0ec61860cdb0c827d3110350fe5d604f4b05bc9 SHA-256: 4ff206fd8c3076c8f9bf1886c329a7ab5906dca06eddff869a7a5c2caee80529
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

This PDF file was flagged by multiple heuristics, including ClamAV and an ML classifier, as malicious phishing content. It employs a link farm strategy with SEO-optimized URLs and redirectors, such as https://pelibifir.ru/123?utm_term=book+of+assistance+arabic+pdf, to entice users to download further malicious content. The presence of external links and the overall structure suggest an attempt to deliver a second-stage payload, likely exploiting a PDF vulnerability.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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://pelibifir.ru/123?utm_term=book+of+assistance+arabic+pdf PDF link annotation
    • http://org-fruit.space/116616763125so2h.pdfIn PDF document text
    • http://zelopaqq.xyz/alexander_video_song19n3m.pdfIn PDF document text
    • https://lanulizuxuja.weebly.com/uploads/1/3/4/6/134658029/5483911.pdfIn PDF document text
    • http://kuvenumine.mygamesonline.org/what_is_an_engineering_notebook.pdfIn PDF document text
    • http://zefutuwukeras.getenjoyment.net/exemple_de_lettre_de_demande_d_attestation_de_stage.pdfIn PDF document text
    • https://federadedeladol.weebly.com/uploads/1/3/4/6/134626130/gisobes_turexi_vulul_baxodif.pdfIn PDF document text
    • http://jonipifenukiz.mygamesonline.org/90947217451.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://disoluje.myartsonline.com/kepinewujafetoredizez.pdfIn PDF document text
    • https://s3.amazonaws.com/vukujidor/game_concept_design_document_template.pdfIn PDF document text
    • https://ac734925-007a-49fa-9a6b-2340142042ec.filesusr.com/ugd/ea78e0_200b5c34bd6d478d98f0491e83a505eb.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/zarelusipofox/mini_blender_with_bottles_how_to_use.pdfIn PDF document text
    • https://s3.amazonaws.com/xelimewat/character_education_worksheet.pdfIn PDF document text
    • https://s3.amazonaws.com/voropa/steam_link_app_ios_beta.pdfIn PDF document text
    • https://748e6e98-33e2-4bd1-95aa-01ea3505a154.filesusr.com/ugd/704f6c_d78472a5437c4f7e964f6fb41643950e.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/xujitezu/33006850014.pdfIn PDF document text
    • https://s3.amazonaws.com/kijelopazekune/ignition_poker_client.pdfIn PDF document text
    • https://s3.amazonaws.com/tubukeganuji/lavefiruzaragutuvebifefe.pdfIn PDF document text
    • https://e7c02ae7-ba66-49ef-8fe7-d4c265c54a1b.filesusr.com/ugd/bc5701_57dd2df9905c4a269dbca81b2180bbdf.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/mojivikapeti/sony_a2300_camera.pdfIn PDF document text
    • https://s3.amazonaws.com/tinezedu/how_to_end_an_essay_conclusion.pdfIn PDF document text
    • https://b760d8db-9746-4821-aa2b-94c9f806d328.filesusr.com/ugd/26ce45_c7f7941f46c04e05ac67a378085374c2.pdf?index=trueIn 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_off0000d75a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD75A 5368 bytes
SHA-256: 0f3249281e46132b061c0d516f0138ebf151a98126c5d62a3fa596dc5a83c21b
font_01_sfnt_off0000e9ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9AD 11120 bytes
SHA-256: 3067922356aa2e4f3a8b664a2d49e58e1095cf8162cdeaf9950f7cddd7529961