Malicious PDF — malware analysis report

Static analysis result for SHA-256 b15d1e281640fcf8…

MALICIOUS

PDF

82.2 KB Created: 2021-09-11 23:53:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 20f8266fdbc8af1588a7faacc23c5906 SHA-1: 1d88c1513c7379af1f9813ce16a2486123a5a8cc SHA-256: b15d1e281640fcf857c40046a6096d5fd9763932c48fd96f5eb4081e38934647
126 Risk Score

Malware Insights

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

The PDF contains a high number of embedded links pointing to various domains, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or distributing further malware. The presence of numerous unknown URLs supports the hypothesis of a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://fsbulletsandbrass.com/userfiles/files/ferivosovosazaxo.pdf
    • http://zamgph.com/uploads/file/090508528672.pdf
    • http://upservice.expert/admin/ckfinder/userfiles/files/tobanifuzafokizazinufegu.pdf
    • http://acelybio.com/upload/files/zuxipovokigasitupivi.pdf
    • http://businessvaluationapp.com/fck_files/file/37289507686.pdf
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/9f12db6ab948898b498aa89c16fb1612/32987948589.pdf
    • https://semineebrasov.ro/printuri-fi/files/40798750716.pdf
    • http://mimarathi.live/assets/ckfinder/core/connector/php/uploads/files/60522813000.pdf
    • https://brawlcall.com/ckfinder/userfiles/files/zonida.pdf
    • https://nakipoglugroup.com/upload/ckfinder/files/68679814235.pdf
    • https://termofriz.rs/files/rebawifawolazud.pdf
    • http://vinhthuan.com/upload/files/3183861139.pdf
    • http://achwvs.love-mrt.com/upload/files/ravetatokenisupumu.pdf
    • http://montaze.org/democms/userfiles/file/11676411924.pdf
    • https://vgcanada.com/userfiles/file/bezipebosozenopuxibobu.pdf
    • http://www.jindatunnel.com/up_files/file/72758445576.pdf
    • https://feriaesotericadeatocha.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a4685a5f39---9822854413.pdf
    • https://idealist.ro/userfiles/file/femobozowefewe.pdf
    • https://dolupin.com/calisma2/files/uploads/74524404642.pdf
    • http://etoprosto.ru/ckfinder/userfiles/files/96272510521.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=descargar+metal+slug+3+apk+full+gratis
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d83f.bin
6b459a417f9f1161cfee5489435269b86903f05ddcc175cd237fe0651767efe8
pdf-font-stream PDF embedded font (sfnt) at offset 0xD83F 19368 bytes
font_01_sfnt_off00010ab4.bin
83c5b56f3a8b2e2e571ecd1d39503b86941b3e97605aa37c2f9950997228f5f1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10AB4 10964 bytes
font_02_sfnt_off0001244d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1244D 16792 bytes