Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e52cb4762040d34…

MALICIOUS

PDF

84.6 KB Created: 2021-09-18 20:10:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 93f0458bf0448cc6576bddcdebaf6515 SHA-1: cd34f494985b10d9af841e8de4935542715b0342 SHA-256: 4e52cb4762040d34b6b7669600f07f6f64209a476ab542c03de5b70f570c5fd3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1055.012 Process Injection T1204.002 Malicious Link

The sample is a PDF document flagged by ClamAV as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS uploads and disposable hosting, suggesting an attempt to lure users to malicious content. The ML classifier also strongly indicated maliciousness.

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
  • 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.
  • 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 https://myagenda.myagenda.cz/pictures/editor/files/35769693863.pdf In PDF document text
    • http://runo34.ru/attachments/file/siwoxofo.pdfIn PDF document text
    • https://encouragingmath.com/wp-content/plugins/super-forms/uploads/php/files/2863db248c093ccaafa1579fd83755be/16674636473.pdfIn PDF document text
    • http://ceramicaartisticamarsalese.it/userfiles/files/liwofobutininax.pdfIn PDF document text
    • https://mimpidia.com/contents/files/kafunigotalobejek.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/1614233323d12a---rirodakabimoxutos.pdfIn PDF document text
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b1e9cd9f24---famivegexanolutuwofekuj.pdfIn PDF document text
    • http://photopuzzle.net/userData/board/file/ninoluwikafowip.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/e49c372038833e57f8445391fd7622ed/renejazezeromoxonuk.pdfIn PDF document text
    • https://www.alapan.org/fckimages/file/diwonutivisozeweteg.pdfIn PDF document text
    • http://ageofwonders.buka.ru/sadm_files/vugupoba.pdfIn PDF document text
    • http://4998horo.gmmwireless.com/contents/files/56203058742.pdfIn PDF document text
    • http://biogenetec.tw/image/files/20210905_213753.pdfIn PDF document text
    • http://wcsps.com.tw/ckfinder/userfiles/files/10941059399.pdfIn PDF document text
    • http://hangtatmj.com/userfiles/dojamelagowejoja.pdfIn PDF document text
    • http://rc-mst.com/mst/_upload/files/dolevejimu.pdfIn PDF document text
    • http://africareview.in/userfiles/file/1956485339.pdfIn PDF document text
    • http://1mosref.ru/ckfinder/userfiles/files/tegizeku.pdfIn PDF document text
    • https://vongtaytramhuong.vn/upload/files/85149742082.pdfIn PDF document text
    • https://happycustomerservice.com/wp-content/plugins/super-forms/uploads/php/files/88aa41496dd35606466e3ff0c9b84035/362339410.pdfIn PDF document text
    • http://carneslaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/35395853610.pdfIn PDF document text
    • https://chatham-ebenezer.ckdomain.com/uploads/userfiles/files/xikixowugugazexogokefew.pdfIn PDF document text
    • http://abwhopewell.com/uploads/files/79932161995.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=0.05+in+to+mmPDF 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_off0000ea93.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA93 9888 bytes
SHA-256: 69a375c85ea2f1dbdbb31735645066f7d8c99883e2c5dd2f213c4c367c1403ca
font_01_sfnt_off00010040.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10040 17352 bytes
SHA-256: eb35532f6fc8a8a8e2507389d528e61929922398df01af4f080cf98e3037d2b8
font_02_sfnt_off00012d6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D6F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1