Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4df7574bdab8847…

MALICIOUS

PDF

76.8 KB Created: 2021-05-24 16:53:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: cf3a139460810b0924179d47a3947e1f SHA-1: 163815c5aad1d08e62c3a1dd32b80561964906bc SHA-256: c4df7574bdab8847e0d25dad524d828c30c61e1187b10b9c0660ae37304107e1
254 Risk Score

Malware Insights

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

This PDF file contains numerous links designed to appear as legitimate resources, but they lead to a malicious redirector. The heuristic firings indicate a deliberate attempt to create a link farm for SEO purposes, likely to phish users under the guise of free downloads. The ML classifier strongly supports the malicious nature of this document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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+practice+english+alone In PDF document text
    • https://nimapefakapag.weebly.com/uploads/1/3/5/3/135324130/47677.pdfIn PDF document text
    • https://gutamunimidujad.weebly.com/uploads/1/3/4/6/134667749/dutufub.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4495409/normal_5fd90431c1b54.pdfIn PDF document text
    • https://xonuguzuv.weebly.com/uploads/1/3/1/3/131382030/cbdfc2.pdfIn PDF document text
    • https://fogunovavak.weebly.com/uploads/1/3/2/6/132681822/ronofenejijid.pdfIn PDF document text
    • https://wezuzasiteva.weebly.com/uploads/1/3/1/3/131397996/7075284.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446382/normal_60642047cd03c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4497110/normal_602f4d295697f.pdfIn PDF document text
    • https://disadoxamegipu.weebly.com/uploads/1/3/4/5/134527150/kupizodu.pdfIn PDF document text
    • https://kumakisatosoref.weebly.com/uploads/1/3/5/3/135328720/zudapetupiviv_navebowu_putomixa_fubobeja.pdfIn PDF document text
    • https://wedutigumufezeb.weebly.com/uploads/1/3/4/6/134659425/8585363.pdfIn PDF document text
    • https://niromegezos.weebly.com/uploads/1/3/2/6/132681660/5029496.pdfIn PDF document text
    • https://vinifobak.weebly.com/uploads/1/3/5/2/135298549/6d1eee.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/zaxefemebidaz/boot_camp_support_software_5._1._5621.pdfIn PDF document text
    • https://s3.amazonaws.com/kikunojulejuj/cuanto_equivale_23_pulgadas_en_centmetros.pdfIn PDF document text
    • https://s3.amazonaws.com/xovekolamoxe/20854789510.pdfIn PDF document text
    • https://s3.amazonaws.com/nosepevozux/50273965929.pdfIn PDF document text
    • https://s3.amazonaws.com/lusabifef/85738125646.pdfIn PDF document text
    • https://s3.amazonaws.com/sesafefanulokam/dinuvifegojubilipe.pdfIn PDF document text
    • https://s3.amazonaws.com/bakoloj/kaxivosivam.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_off0000eeb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEB0 5248 bytes
SHA-256: 817b25f03b686754ff30cc9b185a2d85268111170c16a48d7e1c936fd45ebb1f
font_01_sfnt_off00010092.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10092 10548 bytes
SHA-256: 6f5e293c43ef9c27d82ae6dfc454f5d5e4bbae88b10c6e2d7c29a391f59830e3