Malicious PDF — malware analysis report

Static analysis result for SHA-256 7c457d6397b695c9…

MALICIOUS

PDF

90.5 KB Created: 2021-09-18 06:51:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 64c2c07b58c4fc3fca2afa8536b630b0 SHA-1: 7866e6e06f36e9d5302e1ba49c7644c74895301c SHA-256: 7c457d6397b695c97032d20ff4f2fe60fd72ba95bfa170ee06e4bd94c6765738
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was identified as malicious by ClamAV and an ML classifier, with heuristics indicating embedded JavaScript and a link farm. The embedded JavaScript likely serves to execute malicious actions or redirect the user, while the numerous external URIs point to a link farm designed to obscure the final destination. The presence of embedded JavaScript suggests an attempt to exploit vulnerabilities or perform malicious actions directly within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9910

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://isystem.hu/userfiles/file/dazenawikipopipi.pdf In PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/sedinupadetutod.pdfIn PDF document text
    • http://qianxi.cn/filespath/files/20210917201052.pdfIn PDF document text
    • http://cdseoulps.com/uploadfile/fckeditor/file/wulurukulowoneg.pdfIn PDF document text
    • http://studiocastigli.eu/userfiles/files/josizadarojetofusexo.pdfIn PDF document text
    • http://www.pattyn360.com/upload/forum/files/55304970312.pdfIn PDF document text
    • https://gad-elhak.com/userfiles/file/gevipalenizegegajivape.pdfIn PDF document text
    • http://gemwishrs.com/ckfinder/stones/files/64207873724.pdfIn PDF document text
    • http://nassagroup.org/app/webroot/js/ckfinder/userfiles/files/rowuxu.pdfIn PDF document text
    • http://zsmnowakowski.pl/userfiles/file/75541025739.pdfIn PDF document text
    • https://unifor975.ca/userfiles/file/tivudarazesexapakigebuzo.pdfIn PDF document text
    • http://cecev.com/stockages/files/58748702682.pdfIn PDF document text
    • http://de-ko-gmbh.com/ckfinder/userfiles/files/jabipiwifemuvotunutofiso.pdfIn PDF document text
    • http://rebeccafantarchitetto.it/userfiles/files/wudivojovaj.pdfIn PDF document text
    • http://csc0898.com/userfiles/file/20210912161510_lmbems.pdfIn PDF document text
    • http://hide-bo.com/img/tmp/file/mewuratujigadifa.pdfIn PDF document text
    • http://business-plan-capalpha.fr/mbp/upload/images/images/upload/ckfinder/46012738451.pdfIn PDF document text
    • http://rafaelokazakov.com/file/pitamur.pdfIn PDF document text
    • http://goddesshair.net/upload/users/files/33414192999.pdfIn PDF document text
    • http://cold.lt/userfiles/file/53861160979.pdfIn PDF document text
    • https://vongtaytramhuong.vn/upload/files/kopijejebinusepimu.pdfIn PDF document text
    • https://sahodayabbsr.com/test/fckeditor/file/pegikamum.pdfIn PDF document text
    • https://pianoinprimopianofestival.com/uploads/file/31907814888.pdfIn PDF document text
    • https://derechosenred.org/aym_image/files/4430805125.pdfIn PDF document text
    • http://chinahongji.com/d/files/69771252482.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=yacine+tv+live+for+pcPDF 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d204.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD204 1820 bytes
SHA-256: ef4c56b83544acc0eae329b123dcb13384a4443b8ee25b6b011fcec9f25c534c
font_01_sfnt_off0000da8f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA8F 10352 bytes
SHA-256: beec89e4528742a301b5b2fbcd95af40028ff6b4f7afb3eb38013cfdd459cab6
font_02_sfnt_off0000f211.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF211 24080 bytes
SHA-256: ffc562e091ebf5dc69b3a6def1447197215c09dda0ae945a7c3ffef8057ff29a
font_03_sfnt_off00012deb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12DEB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_04_sfnt_off000145fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x145FC 16128 bytes
SHA-256: e086d997b6ee3c3fe48f8fdf49e8854b9e9bef9c53b5c2c5f26bba4f2b277426