Malicious PDF — malware analysis report

Static analysis result for SHA-256 b49f28885633e71a…

MALICIOUS

PDF

70.9 KB Created: 2021-09-08 06:15:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 3c875a5fdd04cebfb6f02b4ac8329ec6 SHA-1: fc16289c7881ffd47cb328055a746f7342fa268c SHA-256: b49f28885633e71afe37968f58440a3f69d127be41d3410b17345f03c80a4752
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating it likely contains malicious content. The heuristics reveal it functions as a link farm, with numerous embedded URLs pointing to various domains, some of which appear to be compromised or disposable hosting. The primary purpose seems to be directing users to external sites, potentially for phishing or to download further malicious payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://crewmak.ru/uplcv?utm_term=hunter+gatherers+to+farmers+worksheet PDF link annotation
    • https://1877painters.com/FCKeditor/file/48262558513.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/3cfcccb0b32cfa57be1fc3c82058ac18/70036426895.pdfIn PDF document text
    • http://de-ko-gmbh.com/ckfinder/userfiles/files/10371465009.pdfIn PDF document text
    • http://yacpa.org/yacpafiles/file/kafelixapexavowemobizuzup.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16094423073f0a---19080380430.pdfIn PDF document text
    • http://idealhca.com/admin/images/file/18375628532.pdfIn PDF document text
    • http://polesprogettazioni.com/userfiles/files/kurukokamili.pdfIn PDF document text
    • http://koutingchina.com/upload/files/60742056749.pdfIn PDF document text
    • http://www.kotolantopeni.cz/files/53743577401.pdfIn PDF document text
    • http://elma1.ru/!upload/files/47851509061.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160ab2745ab38b---68096941350.pdfIn PDF document text
    • https://healthmatters.me/userfiles/file/77528285994.pdfIn PDF document text
    • http://paintingservicesonline.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161143dc56d70f---lixifunujalaratonadalawit.pdfIn PDF document text
    • https://bcm.es/files/galeria/files/1233938515.pdfIn PDF document text
    • http://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a613800fb9d---gitasolatavazetamutowi.pdfIn PDF document text
    • http://abwva.com/uploads/files/3026765719.pdfIn PDF document text
    • https://medius.sk/userfiles/file/lesokufibu.pdfIn PDF document text
    • http://hungbuloon.com/media/ftp/file/puguluboditasodaxit.pdfIn PDF document text
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/2cfbb1fc94ef1f391ef36adc9476bcc7/zebapefulenalusebow.pdfIn PDF document text
    • https://gemwares.com/userfiles/file/58213993987.pdfIn PDF document text
    • 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_off0000b1a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB1A0 10792 bytes
SHA-256: 859863f4bb8dc5d5e035b4f706f9e87aa7f31205941eab963664f5b6165d369b
font_01_sfnt_off0000ca5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA5B 16980 bytes
SHA-256: 09b0d7a4cbb038141fd2bcc056e3f6eb8ea891d3813e58487482458a1aa94ebc
font_02_sfnt_off0000f61a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF61A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1