Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b06557f962cd35d…

MALICIOUS

PDF

77.7 KB Created: 2021-05-24 14:12:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 82042a0190014cd9a0b0d86c6caf3b1d SHA-1: cfa6a43399ccf290454921a35f2c159181c344b8 SHA-256: 8b06557f962cd35da0c0a457d2a8cd136cb71a0e2c1a8a935ff8e9e318220aba
196 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including PDF_SEO_LINK_FARM and PDF_SEO_UTM_REDIRECTOR_LINK, indicating it contains a large number of external links designed to redirect users to malicious sites. The ML classifier and ClamAV also identified it as malicious, specifically a phishing trojan. The embedded URLs, such as https://midufefew.ru/strik, are likely used to host phishing pages or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://midufefew.ru/strik?utm_term=what+is+the+message+of+fences PDF link annotation
    • https://zinexosodolawiw.weebly.com/uploads/1/3/4/2/134235462/4483425.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4461770/normal_6041e6b1f1c92.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4418185/normal_602411a1d8378.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443594/normal_601dab237076f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408720/normal_603391eb7ce86.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485445/normal_60644ab978004.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4480580/normal_5fe68cd5601f9.pdfIn PDF document text
    • https://tujemodi.weebly.com/uploads/1/3/5/3/135301643/putufe.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4478383/normal_6033802d91d8d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453329/normal_603650a01a595.pdfIn PDF document text
    • https://wubugivaruj.weebly.com/uploads/1/3/4/6/134669137/8c93da34d2eb859.pdfIn PDF document text
    • https://zavexirated.weebly.com/uploads/1/3/2/6/132695663/buxejinivu_kuridomode.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4426820/normal_6050f1597ab3b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4406170/normal_5fea005a0032b.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/gofiguj/speech_ideas_for_middle_schoolers.pdfIn PDF document text
    • https://s3.amazonaws.com/fuwuzerijofa/current_affairs_mcqs_with_answers_of_pakistan.pdfIn PDF document text
    • https://s3.amazonaws.com/mokuwanibof/nekutadajape.pdfIn PDF document text
    • https://s3.amazonaws.com/safenalavojuwu/bike_computer_app_for_android.pdfIn PDF document text
    • https://s3.amazonaws.com/gedexim/89800894374.pdfIn PDF document text
    • https://s3.amazonaws.com/wovitiku/carbonite_backup_software.pdfIn PDF document text
    • https://s3.amazonaws.com/gulapore/57461239494.pdfIn PDF document text
    • https://s3.amazonaws.com/bidurudilidujug/zases.pdfIn PDF document text
    • https://s3.amazonaws.com/nuruvapozixix/rafukefazotasepezekofonex.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_off0000f114.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF114 5180 bytes
SHA-256: d2f012665275c72f9a7d86b80a0ebe431f732819718d0ca6bd682e5eda51569f
font_01_sfnt_off000102a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x102A4 10980 bytes
SHA-256: b38d9cf5c18f0b3d30e26c393525eb74d29af4f6765b06e67893267a0bb659a4