Malicious PDF — malware analysis report

Static analysis result for SHA-256 8766ec69c98dab08…

MALICIOUS

PDF

78.0 KB Created: 2021-04-09 04:12:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 430af6f4a8982bdac8d583b674f4d04e SHA-1: 6d117adc2193097821f6a0c34cda70763f43df6e SHA-256: 8766ec69c98dab0872e3e0ce9e5055710978dc28fed20055840027984decd4b1
196 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to SEO-optimized content, suggesting a link farm or phishing lure. The primary URL, 'https://pelibifir.ru/strik?utm_term=caps+for+sale+book+online', is flagged as a redirector for a 'free-download phishing' attempt. ClamAV detection and ML classification confirm the malicious nature, identifying it as 'Pdf.Phishing.Trojan'. No scripts were extracted, but the structure indicates a malicious document designed to redirect users to a potentially harmful site.

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.
  • 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/strik?utm_term=caps+for+sale+book+online PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4489255/normal_604162f127be3.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446165/normal_601ef1cf63a52.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4493282/normal_60567be0b94be.pdfIn PDF document text
    • https://nezokamovijemi.weebly.com/uploads/1/3/1/8/131856769/sosisovev.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4426279/normal_5feb716b87d75.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4422906/normal_604bba2a6d5b2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474979/normal_606e3311c0c14.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403129/normal_605336d22e781.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4503279/normal_606d91da39227.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4484364/normal_5ffd9e3b373e7.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4384307/normal_6005ba9c2a3a5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4447880/normal_6050e0cf2a694.pdfIn PDF document text
    • https://debexubomes.weebly.com/uploads/1/3/4/8/134881130/5831072.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367294/normal_605ffe13a58b4.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4502188/normal_603dfcd2cdf66.pdfIn PDF document text
    • https://riviruzo.weebly.com/uploads/1/3/0/7/130739493/sivir_pagogej.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4367905/normal_600a909243941.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416939/normal_600b5ed75a9ef.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/veraxawewib/video_er_app_for_android_2018.pdfIn PDF document text
    • https://s3.amazonaws.com/fokapikow/kijugofebedisesulud.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_off0000f64c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF64C 5004 bytes
SHA-256: cc6f730bee9ba03716128c883441a85b509cc6d2f9488edb90d803799c235550
font_01_sfnt_off00010757.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10757 10300 bytes
SHA-256: 03ff31668025eb9ea1423df0a3704f9708085476d0fa1971414b1753b53b6bfe