Malicious PDF — malware analysis report

Static analysis result for SHA-256 2cebef12fa7868a6…

MALICIOUS

PDF

115.8 KB Created: 2021-02-18 00:01:33 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 9905ab1a293186f0eb1c437928e3c99a SHA-1: dfa3e72baae842aedf73e56066535d948e4b1ff0 SHA-256: 2cebef12fa7868a62b250e19dc81fd9f2d992d0fe7c8340a7925d7e1fbbd2e6d
144 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it's an advance-fee scam lure. The document body, though heavily obfuscated, suggests a theme of 'natural selection worksheet pdf answers', likely a pretext to encourage downloading a malicious payload from one of the embedded URLs. The presence of multiple external URIs further supports the download-and-execute attack pattern.

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
  • Advance-fee lottery/parcel scam lure high SE_ADVANCE_FEE_SCAM_LURE
    Document contains lottery/beneficiary or prize language together with large-value draft/funds wording and parcel/courier delivery requirements. This is a classic advance-fee fraud document shape.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://bologen.ru/wix?keyword=natural+selection+worksheet+pdf+answers
    • https://cdn-cms.f-static.net/uploads/4485942/normal_60237e5fdb21e.pdf
    • http://fuckfrsky.com/background_color_android_studio_xml5o2e6.pdf
    • https://static.s123-cdn-static.com/uploads/4408176/normal_5ff5380c38f15.pdf
    • http://wow50.pro/86559906622j699z.pdf
    • http://lnstagramcopyrightcenter.com/assir_mataro_cita_previas6d5k.pdf
    • https://cdn-cms.f-static.net/uploads/4488556/normal_60273c874c1ab.pdf
    • https://static.s123-cdn-static.com/uploads/4408862/normal_5fcd6cb4162d4.pdf
    • https://cdn-cms.f-static.net/uploads/4475392/normal_6029e8e467032.pdf
    • https://static.s123-cdn-static.com/uploads/4479474/normal_5fe20086a7588.pdf
    • http://chestlune.online/amman_thalattu_kummi_pattu0wczg.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://xofafatererowu.rf.gd/dovilenofinaburetexonona.pdf
    • http://zegudonokor.epizy.com/82181004366.pdf
    • http://nivewurunowu.rf.gd/arobnjak_iz_oza.pdf
    • http://dixadenidufudu.epizy.com/regakeduwopanufeduzariki.pdf
    • 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://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000188a6.bin
f555a459a0f45b181a4481322bc0b4d30d60e5891a357b4280181651c3515186
pdf-font-stream PDF embedded font (sfnt) at offset 0x188A6 5368 bytes
font_01_sfnt_off00019afc.bin
6427b6ed0511da4620f7bc3f0978d303328db8ded5ab018a3c68f57d21fb76a9
pdf-font-stream PDF embedded font (sfnt) at offset 0x19AFC 11760 bytes