Malicious PDF — malware analysis report

Static analysis result for SHA-256 ea798a56817fda9c…

MALICIOUS

PDF

87.1 KB Created: 2021-09-22 22:33:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 17c1e683ca00368b9de23f8343ea9100 SHA-1: 9f61fa1b723cfa46415564df0434d3f912c0612a SHA-256: ea798a56817fda9c50abc606e774f8563eab328814684d898be97e8a737b162a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a significant number of external links, many hosted on compromised or disposable domains, indicating a link farm designed to obscure the final destination. ClamAV and ML classifiers flagged this as malicious, with the embedded JavaScript likely serving to execute malicious code or redirect the user. The presence of a link farm on compromised WordPress uploads suggests an attempt to distribute malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/16134c081df10a---51225602518.pdf In PDF document text
    • http://vet-spb.com/userfiles/file/88430085441.pdfIn PDF document text
    • http://perchegouet.com/ckfinder/userfiles/files/8917135370.pdfIn PDF document text
    • https://pasarantogel2.com/contents/files/58880016213.pdfIn PDF document text
    • https://webdatedepot.com/userfiles/file/pirafakudunutobavojas.pdfIn PDF document text
    • https://gastrotest.co/ckfinder/userfiles/files/58490168985.pdfIn PDF document text
    • https://www.jakketoes.be/ckfinder/userfiles/files/bawagasixuj.pdfIn PDF document text
    • http://www.binghan.my/userfiles/file/33779856042.pdfIn PDF document text
    • https://vgi-vn.vn/app/webroot/img/files/semosilixuzuzilav.pdfIn PDF document text
    • https://www.afoa.org.ar/backend/ckfinder/userfiles/files/nujedokafedowob.pdfIn PDF document text
    • https://manorhair.com/uploads/files/202109170809093303.pdfIn PDF document text
    • https://patriot.ch/wp-content/plugins/super-forms/uploads/php/files/md2kaklon0otmgpmkcsfof42uc/5860467493.pdfIn PDF document text
    • http://lab4050.com/upload/editor/file/40390361172.pdfIn PDF document text
    • https://mimpidia.com/contents/files/nigowisixadok.pdfIn PDF document text
    • https://segurosjdd.com/wp-content/plugins/super-forms/uploads/php/files/oht0kkgli31gkc481bu3d0bho1/22726403376.pdfIn PDF document text
    • http://kleinschaden-expert.com/userfiles/file/80564275514.pdfIn PDF document text
    • http://jayeonrak.com/upfile_editor/2021/files/tufitojavimexurejile.pdfIn PDF document text
    • http://fioredda.com/userfiles/files/vidosinapadum.pdfIn PDF document text
    • http://cps-mbstu.edu.bd/app/webroot/js/ckfinder/userfiles/files/7852727031.pdfIn PDF document text
    • http://www.museopizarra.com/ckfinder/userfiles/files/80493059468.pdfIn PDF document text
    • http://luxmeterthai.com/ckfinder/userfiles/files/76591933200.pdfIn PDF document text
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137379711f2b---katokegow.pdfIn PDF document text
    • https://stauber.lt/images/files/20771910207.pdfIn PDF document text
    • http://vatlieulamnha.com/media/ftp/file/22180594721.pdfIn PDF document text
    • http://xn--90aoj0agf7cq.xn--p1ai/uploads/files/zubaxotebuweva.pdfIn PDF document text
    • http://93564497.com/userfiles/jugedovinemidebazanif.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=all+bangla+newspaper+list+of+bangladeshPDF 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_off0000efbc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFBC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000107d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107D3 10984 bytes
SHA-256: 5adbddf5c55c988f3e8b85cb82340c53e3a7003d8edb0262bd2a063c0d2b0049
font_02_sfnt_off000120ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120EF 17600 bytes
SHA-256: a9a159e1686c19e3994ba66eb364cd6e81612ff1ebad7a149ecca2b21b234147