Malicious PDF — malware analysis report

Static analysis result for SHA-256 d8766143142d0b20…

MALICIOUS

PDF

73.8 KB Created: 2021-09-26 18:45:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 68924ab85e5e122258b203a675da7bb2 SHA-1: 2beb438d5ee17366b50ccdac24bcb5b3b379c0b7 SHA-256: d8766143142d0b20b86fe99af8fa3e120d3ddbe85324fc5233cabf6f8f17f15c
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript likely redirects the user to one of the numerous external URLs found in the document, which are often used for phishing or to download further malicious payloads. The presence of many distinct hosts and URLs suggests a link farm designed to obscure the ultimate destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://1544-7419.net/upload/fckeditor/file/76602143578.pdf In PDF document text
    • http://inannamsao.com/uploads/files/91550730485.pdfIn PDF document text
    • https://bold-iot.com/uploads/files/202109192003393131.pdfIn PDF document text
    • https://shrmivirtual.org/wp-content/plugins/super-forms/uploads/php/files/16a4a044f9295091ceb752ce9093e80a/88016357423.pdfIn PDF document text
    • http://rivebistro.net/ckfinder/userfiles/files/gefinupulurilexo.pdfIn PDF document text
    • https://marlin-shop.ru/ckfinder/userfiles/files/91685427990.pdfIn PDF document text
    • https://dennismaloney.ca/upload/editor/file/mifalusut.pdfIn PDF document text
    • https://institutdesante.org/userfiles/file/65792652714.pdfIn PDF document text
    • http://telektrans.hu/editor_up/kebotal.pdfIn PDF document text
    • http://bcslaw.hu/admin/fck_upload/file/52726793771.pdfIn PDF document text
    • http://sten.kr/club/data/userfiles/file/20210916044459.pdfIn PDF document text
    • http://yoga-privates.com/yoga-privates/file/85862315093.pdfIn PDF document text
    • http://keramann.ru/uploads/files/vizuwugudojezuziguj.pdfIn PDF document text
    • https://hardlineconstruct.ro/app/webroot/files/userfiles/files/83997281285.pdfIn PDF document text
    • http://nature-revive.org/files/file/88552195995.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/4e0199145dfee94148dd80e18e089eb6/reteninuwuzo.pdfIn PDF document text
    • https://fpcofmacon.com/nbloom/fckuploads/file/finezimevidono.pdfIn PDF document text
    • http://burningspearmarketplace.com/js/ckfinder/userfiles/files/73442143208.pdfIn PDF document text
    • http://files.ibiza-ferien.de/file/48536304450.pdfIn PDF document text
    • https://windscrm.net/files/file/mutenujep.pdfIn PDF document text
    • http://physocare.com/Images_upload/files/9751380431.pdfIn PDF document text
    • https://lenaoyunlar.net/calisma2/files/uploads/monukunanaz.pdfIn PDF document text
    • http://cctechlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/30161168409.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=he%27s+not+that+into+you+pdfPDF 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_off0000baec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBAEC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d303.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD303 10688 bytes
SHA-256: 36c086867179333c35d85bdfb1159f621e029855aef78506793f2525b22204d8
font_02_sfnt_off0000eb7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB7C 17872 bytes
SHA-256: 01d7a33bc4787e1de573b40c5ac0587f0bd77cb206368ae4a5738b2c0c5d4208