Malicious PDF — malware analysis report

Static analysis result for SHA-256 6bdcaf3f555c8c79…

MALICIOUS

PDF

79.0 KB Created: 2021-05-26 20:17:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 87b8d35ab2fa31fef75bfd5bef4abd34 SHA-1: 22418024e2d544d11a4758cf42c3a647f1b95c3d SHA-256: 6bdcaf3f555c8c7986fd5cf12b9ee53f6e4c1157c5d5b248f5ce0fd545346288
196 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics, including ClamAV and an ML classifier, as malicious. It contains a mass external link farm and an SEO redirector pointing to the URL https://kuzutuzo.ru/strik?utm_term=amazon+kindle+fire+7+android+version. The document body, though heavily obfuscated, contains references to 'Amazon kindle fire 7 android version', suggesting a lure to attract users interested in that topic. The presence of embedded links and the overall structure indicate a phishing or malware distribution attempt.

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
  • 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://kuzutuzo.ru/strik?utm_term=amazon+kindle+fire+7+android+version PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4465263/normal_60079ef79d30b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4458137/normal_601cacc611611.pdfIn PDF document text
    • https://vidufatow.weebly.com/uploads/1/3/1/4/131438098/1634865.pdfIn PDF document text
    • https://xijananok.weebly.com/uploads/1/3/0/7/130740199/5580754.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4368953/normal_6007cd9bb1cfa.pdfIn PDF document text
    • https://girenofozajete.weebly.com/uploads/1/3/4/4/134476001/luvogejogazokuxe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4479451/normal_601a19112b1ba.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4380211/normal_6057aa0f565ad.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/e07946b2-e56a-42e4-b739-53633c34adaf/wiwepadunitejiwujitapev.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/16354cfc-5788-49e8-95e7-8e8107559fd9/nogezuworakezilimopudu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/9b96d83a-ee63-49b0-a01d-97025d3f44e1/who_sells_honda_generators_in_my_area.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/83595d97-2ed3-4c24-a635-fb199bce39d5/7590025916.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/49805fef-5d5a-4f70-8513-9321e74ee14e/23138771173.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4604730b-5c1a-45ff-95ee-f0421c1bbf75/felofosazanukelurinuti.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3f25da38-66bd-4212-a190-dca4110ad8f6/jesof.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/931f7326-376f-4dbf-8bbc-01d8024cb417/thank_you_maam_answers_commonlit.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e6930618-4bf4-4fed-b598-fdb82ec96557/47463734530.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a595ed92-731b-4ba8-958f-53d364901e78/16674057095.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/80d2ce1b-f96d-4118-b5c9-6ccd24bb96ec/wefoselajajofonuwezaxe.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b2222936-984a-40e7-9710-aaab806401b4/keller_excellence_250_ficha_tecnica.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0839de95-982a-4197-bfb3-ddf2b5cb6af5/jobogarejipexos.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_off0000f777.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF777 5296 bytes
SHA-256: 0c091599432d3d4e960ce7b00f737e75af193cf5123a4c7acb0619a87c126864
font_01_sfnt_off00010978.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10978 10804 bytes
SHA-256: 20f971f7047a851f35b445002d079f11d3e86b9d3fd03dbf9e1e99ad8f4b6c4e