Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb3bc298747fdd45…

MALICIOUS

PDF

70.0 KB Created: 2021-09-24 13:09:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 00adef82982bc9137c5f2064fadb75b8 SHA-1: 16ea46318ff6e07c17a80a7233b40f9c54aea737 SHA-256: cb3bc298747fdd457d7d636fa548a79921af83a985ba564635087a9a3acac0b4
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by a machine learning classifier and ClamAV as malicious, with a high probability of being a phishing or trojan. The presence of embedded JavaScript and numerous external URIs, many pointing to potentially disposable domains, indicates an attempt to lure users to malicious sites. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, suggesting a link farm designed for SEO manipulation or redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://eyela.kr/uploadfile/fckeditor/file/47539344323.pdf In PDF document text
    • http://www.phsdcenter.com/temp/js/ckfinder/userfiles/files/84707877389.pdfIn PDF document text
    • https://thegioibaobicarton.com/Images_upload/files/toxuvikila.pdfIn PDF document text
    • http://flashdisplay.net/UploadFiles/FCKeditor/20210919180510.pdfIn PDF document text
    • https://stcc-sa.com/motakamel/Ups/files/31914357607.pdfIn PDF document text
    • https://dansobentre.net/uploads/file/26465896590.pdfIn PDF document text
    • http://mcrlclient.gilcom.ro/ckfinder/userfiles/files/dezosuzisifazum.pdfIn PDF document text
    • https://www.habitat-morvan.fr/ckfinder/userfiles/files/jijulafozajimodobizufos.pdfIn PDF document text
    • http://wxmx.cn/upload/ckimg/files/202109030647324133.pdfIn PDF document text
    • https://ceccarmehedinti.ro/userfiles/file/furataxukufolosisepe.pdfIn PDF document text
    • http://fuli-capital.com/userfiles/file/dizomapowodedimusibaje.pdfIn PDF document text
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613478618a6c9---58205894503.pdfIn PDF document text
    • http://giasuminhtam.com/Images_upload/files/18931640839.pdfIn PDF document text
    • http://exdebt.bg/userfiles/file/53777141677.pdfIn PDF document text
    • http://psycare-spb.com/userfiles/file/3971457907.pdfIn PDF document text
    • http://xn--o79av69abka850ab6c.com/upload/file/202109061551258425.pdfIn PDF document text
    • http://freehajjandumrah.com/admin/admin/uploadfiles/file/zebide.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/161434d093abdd---pamedawelumajusoduxome.pdfIn PDF document text
    • http://orikon.net/Images_upload/files/zopubexefizak.pdfIn PDF document text
    • http://leaguengn.com/userfiles/file///xozix.pdfIn PDF document text
    • https://pmcp-avac.com/files/upload-ckfinder/files/vuzilusewazufakewasora.pdfIn PDF document text
    • http://karate-talence.com/newsite/userfiles/files/62924378517.pdfIn PDF document text
    • http://1night2day.com/UserFiles/file/25373578483.pdfIn PDF document text
    • http://hit-air.pro/ckfinder/userfiles/files/61219743990.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=android+how+to+clear+clipboardPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b14b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB14B 10648 bytes
SHA-256: 78e0775e8ea58915dd4fe303ff5f2712c29e4e0df1ac0660ca4c13218e06f15a
font_01_sfnt_off0000c963.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC963 16032 bytes
SHA-256: 41d32ddd9f2a6446142045944229f924f5b6d93b08270eeb90aaef1aa190249d
font_02_sfnt_off0000f295.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF295 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1