Malicious PDF — malware analysis report

Static analysis result for SHA-256 ce1ff6a10a1483a2…

MALICIOUS

PDF

67.8 KB Created: 2021-09-21 22:11:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: b8bd66ec2784dd8405c0f0a14f45674b SHA-1: 42d23e73a7d6bce8cac0634fa703d6e5c8b091d5 SHA-256: ce1ff6a10a1483a2e060d04f09563e1497047036a48d2fd77179b9bdd23e1bc1
134 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and a high number of external URIs pointing to disposable hosting, indicative of a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to deliver a second-stage payload or facilitate phishing. The presence of embedded JS points to exploitation for client execution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://scbczy.cn/up_files/file/20210911_130543.pdf In PDF document text
    • https://spirit-legend-enterprises.com/webroot/editor-uploads/files/47690552229.pdfIn PDF document text
    • https://capital-publishing.com/ckfinder/userfiles/files/76486727439.pdfIn PDF document text
    • https://atputasbaze.lv/images/userfiles/files/luxegunurosa.pdfIn PDF document text
    • https://postelezmasivu-zlin.cz/ckfinder/userfiles/files/15884242653.pdfIn PDF document text
    • http://teewer.mn/ckfinder/userfiles/files/70255662418.pdfIn PDF document text
    • http://zhongjiukeji.com/upload_fck/file/2021-9-14/20210914175237311619.pdfIn PDF document text
    • https://12waktu.com/contents/files/32154157853.pdfIn PDF document text
    • http://guoyangmoju.com/userfiles/files/wunadesulirujojifom.pdfIn PDF document text
    • http://co-mit.com/uploads/files/9645789439.pdfIn PDF document text
    • http://ginzaoakland.com/uploads/files/7079729797.pdfIn PDF document text
    • https://www.santaterezinha.com.br/js/ckfinder/userfiles/files/70762818049.pdfIn PDF document text
    • http://volkshilfe-ktn.at/images/content/files/povaderutonarojepanuxivir.pdfIn PDF document text
    • http://francescofesta.it/userfiles/files/raralaxifomurirezubof.pdfIn PDF document text
    • https://varida-tech.com/ckfinder/userfiles/files/mulilipotabekaza.pdfIn PDF document text
    • http://nguyenthaotech.com/upload/files/faranoxorukan.pdfIn PDF document text
    • https://www.frontiermea.com/sites/all/libraries/ckfinder/userfiles/files/xogeseponazuzine.pdfIn PDF document text
    • https://medarbindia.org/ckfinder/userfiles/files/rufekulalez.pdfIn PDF document text
    • https://rubfila.in/files/file/miforifedegajizuk.pdfIn PDF document text
    • http://yomamasushitogo.com/uploads/files/31033175261.pdfIn PDF document text
    • https://pushtypathshala.com/demo/aims/files/images/files/33121941484.pdfIn PDF document text
    • https://lbjgold.in/ckfinder/userfiles/files/67938691828.pdfIn PDF document text
    • http://doctour.hu/uploads/ckfinder/userfiles/files/85916117674.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=download+mobomarket+for+android+apkPDF 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_off0000ad62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD62 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c574.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC574 14368 bytes
SHA-256: df46fe21a8c2a12b4070d4b06b93e25f42ed641228a3892d200bb3ca49a49019
font_02_sfnt_off0000e940.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE940 10812 bytes
SHA-256: f8d68cf31ae3653fa13221c352f1072464ac8e5caf656e3930349ecc91abe966