Malicious PDF — malware analysis report

Static analysis result for SHA-256 9d951bbc42b6a0ab…

MALICIOUS

PDF

69.6 KB Created: 2021-09-29 02:44:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 811cbfedd2043397062f67efe6149ae9 SHA-1: ff8279c473e62ac1b43745725a5cb24e1fc86ac8 SHA-256: 9d951bbc42b6a0ab547d666d269dd63d12a3550ee761fb845357e316260e57a8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was flagged by multiple heuristics as malicious, including a high-confidence ML classification and a ClamAV detection for a phishing trojan. The file contains a link farm pointing to numerous disposable domains and compromised CMS upload storage, indicating an attempt to direct users to malicious content. The document body is heavily obfuscated and unreadable, suggesting it is designed to conceal its malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

Heuristics 6

  • 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.
  • 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.optimizecost.com/admin/ficheros_fckedit_subidos/23889833222.pdf In PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b0ee06e34e---549756556.pdfIn PDF document text
    • https://beaszemin.com/files/fimuneromepedunifiv.pdfIn PDF document text
    • https://doina.md/fckeditorfiles/file/27400552042.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1614c0af2dc8ac---69471737667.pdfIn PDF document text
    • https://bohemiamaestro.com/webpagebuilder/ckfinder/userfiles/files/jesuzevi.pdfIn PDF document text
    • https://lifecareproduct.in/ckfinder/userfiles/files/47523706908.pdfIn PDF document text
    • https://www.esfa.bg/root/ckfinder/userfiles/files/9440832528.pdfIn PDF document text
    • https://juniorclublivorno.com/sitonews/images_upload/files/diwuzozalitanitemu.pdfIn PDF document text
    • http://mosjob.ru/images/file/82783176583.pdfIn PDF document text
    • https://protrialse.eu/files/files/91456682987.pdfIn PDF document text
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/e221ca96e37cb3e50cf5edfb89e44a0b/26168337720.pdfIn PDF document text
    • http://allegroescrow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147f84e659e6---23440928397.pdfIn PDF document text
    • https://www.tcf.gov.tr/ckfinder/userfiles/files/11134472385.pdfIn PDF document text
    • https://sieuviet.net/webroot/img/files/88404403504.pdfIn PDF document text
    • http://sourceandsecure.com/uploads/userfiles/file/62391360796.pdfIn PDF document text
    • http://agenziaimmobiliarecannavo.eu/userfiles/files/80877360796.pdfIn PDF document text
    • http://theeultimatenetworker.com/ckfinder/userfiles/files/vewokifumagotulasenorep.pdfIn PDF document text
    • https://kawanmto.info/contents/files/99625489841.pdfIn PDF document text
    • http://sabaparsian.com/ckeditor/files/files/44775532124.pdfIn PDF document text
    • https://www.libyamonitor.com/sites/all/libraries/ckfinder/userfiles/files/43631849030.pdfIn PDF document text
    • http://ldksolar-officialliquidation.com/userfiles/files/19372756606.pdfIn PDF document text
    • https://piphoto.tw/uploads/files/202109191722575809.pdfIn PDF document text
    • http://nhactheducthammy.com/upload/files/71217382941.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=taskmaster+us+s01e01+watch+onlinePDF 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_off0000b097.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB097 15068 bytes
SHA-256: be9bdabd02ee644a819f437aecaa702efadb68b04535088d14b414a1cb0a7688
font_01_sfnt_off0000d6cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD6CC 10912 bytes
SHA-256: 773c2e24d109f8a9848106ab944b6423e18b7742087eaaed1addf6efe86494aa
font_02_sfnt_off0000effd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFFD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1