Malicious PDF — malware analysis report

Static analysis result for SHA-256 259f681ebbace8ec…

MALICIOUS

PDF

74.6 KB Created: 2021-09-11 18:35:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 57c2f20bf09ec5839887dbff4424bbdb SHA-1: 0dbc9b3b508de39bc111a9b5e22feb8933db1d8c SHA-256: 259f681ebbace8ec35d3e45ab12fc2dc0e50a8eb96d310ccf98097ba96e76b83
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external URLs hosted on potentially compromised or disposable domains. The presence of numerous PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM firings strongly suggests the document's primary purpose is to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

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://es21sys.com/userfiles/file/xifoxelafakagetabapilu.pdf In PDF document text
    • https://artlabjo.com/userfiles/file/39145974971.pdfIn PDF document text
    • http://embeddedhr.com/ckfinder/userfiles/files/88059004016.pdfIn PDF document text
    • http://dgxzz.com/uploadfile/file/49499686411.pdfIn PDF document text
    • http://telegid.tv/userfiles/file/paxeloxejagunipiforumapop.pdfIn PDF document text
    • https://apexsafetyproducts.com/ckfinder/userfiles/files/63359935753.pdfIn PDF document text
    • http://crocepadrekolbe.it/userfiles/files/73910242183.pdfIn PDF document text
    • http://stomerijindex.nl/images/uploads/28196426543.pdfIn PDF document text
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/161327d89c9ba4---53363089456.pdfIn PDF document text
    • http://webbyshoe.com/fckeditor/userfiles/file/33911160832.pdfIn PDF document text
    • https://thailonghoang.vn/upload/files/fejizij.pdfIn PDF document text
    • http://www.yankey.com.tw/demo/public/editor/ckfinder/upload/user_upload/files/64291019554.pdfIn PDF document text
    • http://dobryremont.pl/ebobas/portal/app/webroot/img/tmp/file/16312661758611.pdfIn PDF document text
    • http://nuk-amro.de/userfiles/file/17162900247.pdfIn PDF document text
    • https://n-v-v.dk/userfiles/file/wutipalabesix.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/a9f33b39d08c6a9104820ce62cb7b3d3/matugumo.pdfIn PDF document text
    • http://alltechsro.cz/files/96441534331.pdfIn PDF document text
    • http://audidalys.lt/ckfinder/userfiles/files/vesuku.pdfIn PDF document text
    • https://delaneyllc.cfonewsletter.com/ckfinder/userfiles/files/ziketatori.pdfIn PDF document text
    • https://campermagazine.tv/public/file/tevifurufutururirewe.pdfIn PDF document text
    • http://ourconn.com/userfiles/file/202109040639329766.pdfIn PDF document text
    • http://viaterrestre.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613a229470750---fojogogakebetubofefejegip.pdfIn PDF document text
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161326eb4c624b---gozoferoxis.pdfIn PDF document text
    • http://chukysovin.com/img-svc/files/mesosexe.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/13217905931.pdfIn PDF document text
    • http://veganogle.es/uploads/ckfinder/files/88709805232.pdfIn PDF document text
    • https://hoangvan.vn/wp-content/uploads/files/rowawowekumusitaz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=carrom+strike+mods+of+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_off0000c05d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC05D 10632 bytes
SHA-256: 1cd7886beb5101da0bf1c6c4585cbe87c64ac15a9b7a0f638c4a19da1235bbeb
font_01_sfnt_off0000d8bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8BF 17024 bytes
SHA-256: 0a59a7d3bac06b59a9d2de6381e253a2682c2fc98e4b04d9382b2dd918a05ae0
font_02_sfnt_off000104c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1