Malicious PDF — malware analysis report

Static analysis result for SHA-256 f830e935fbaacd76…

MALICIOUS

PDF

87.2 KB Created: 2021-10-21 20:46:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 683de15394aa5eb2e87e2b5d3435adb3 SHA-1: 5f965bb7dd84ee7683097f28b4942a3f0337ba17 SHA-256: f830e935fbaacd76573eb23ab9fb5b2507ed4a8bcd586eca50c37cd9fc086de4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for initiating malicious actions. The heuristic firings indicate the presence of a link farm pointing to compromised websites, suggesting the document is part of a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly support the malicious nature of this file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. 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://mlead.net/images/e/file/30167703099.pdf In PDF document text
    • http://chipgene.com/image/files/20210927_125803.pdfIn PDF document text
    • http://bckvalumni.org/userfiles/file/60570081408.pdfIn PDF document text
    • https://www.zaantraining.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161698117d8dd2---digujolojo.pdfIn PDF document text
    • http://www.de.ruben.pl/ckfinder/userfiles/files/pagitojiwefezukejamot.pdfIn PDF document text
    • http://www.ciesol.es/ckfinder/userfiles/files/devodeve.pdfIn PDF document text
    • https://segurodegranizo.ar/noticias/fckeditor/file/vopesoresolita.pdfIn PDF document text
    • http://pegasomeeting.medcoast.net/ckfinder/userfiles/files/nisenomokitoraf.pdfIn PDF document text
    • https://korvioinfotech.com/ckfinder/userfiles/files/63750955771.pdfIn PDF document text
    • http://kammed.com/userfiles/file/92134486441.pdfIn PDF document text
    • http://hawaiisushi.iorderfoods.com/uploads/files/vivujidexip.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/su182e1kj6mgs01c95capgks35/93504436067.pdfIn PDF document text
    • http://sushiloverca.com/uploads/files/62978185873.pdfIn PDF document text
    • https://ganganagardentist.com/userfiles/file/40115332190.pdfIn PDF document text
    • http://indianmailbox.com/assets/images/userfiles/files/55165123607.pdfIn PDF document text
    • https://www.aledrukujemy.pl/ckfinder/userfiles/files/85724946040.pdfIn PDF document text
    • https://www.multilandtours.com/assets/ckfinder/userfiles/files/tajak.pdfIn PDF document text
    • http://fundacjaproartis.pl/javascript/ckfinder/userfiles/files/fupaliru.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/16137e2fd28d48---71241990766.pdfIn PDF document text
    • https://www.tratedu.net/ssss2018/assets/143ad273/ckfinder/core/connector/php/upload/userfiles/files/ef79aa6977cd48a8a57aa2f2bbf873e1.pdfIn PDF document text
    • http://erfanekeshmiri.ir/userfiles/file/26246143022.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Gsjc/~3/2I9n2o-U8HI/uplcv?utm_term=little+baby+crying+soundPDF 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_off0000f0f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0F5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010907.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10907 17296 bytes
SHA-256: dbcb462ffff38606f1a68f449b49fe5634c1d2104a1520b7216eac96f7395fbc
font_02_sfnt_off00013607.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13607 10856 bytes
SHA-256: 01971808ab6c624d2ffaefbdf0230ebc9d7a5184c0068d29b29f0be934145974