Malicious PDF — malware analysis report

Static analysis result for SHA-256 6f9bd3839415fd79…

MALICIOUS

PDF

73.7 KB Created: 2021-06-22 14:19:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 6c65f9a85a6ffe22791c333a21aea869 SHA-1: 1425242d9df3b052ba6199698303032a1de85cf9 SHA-256: 6f9bd3839415fd795a6638a8dfb81c481ab1140b184cde737177c57a2d5e9101
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed for malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. No scripts were extracted, but the structure and URL analysis point to a common tactic of using documents as a lure to external malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

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 http://optikametuje.cz/userfiles/file/nuvunulijop.pdf In PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/b1ef697a21a6fda2190bfcc0c96a6b40/fuzinepotogukojanu.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/160cba1c49f7bf---fogugog.pdfIn PDF document text
    • http://shinies.ru/img/lib/file/78312127926.pdfIn PDF document text
    • https://drmiamiconnect.com/wp-content/plugins/super-forms/uploads/php/files/9b86fe134f1f5685f22f373d9f7e9f96/82140605449.pdfIn PDF document text
    • https://www.webplease.it/wp-content/plugins/super-forms/uploads/php/files/eeqbg6q7rm0fm0qfsggtr6rodl/najupezoxosixonugi.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16073ce79a4331---pakejixeraki.pdfIn PDF document text
    • https://agsposure.org/wp-content/plugins/super-forms/uploads/php/files/629d87d1939731d990c11f7f8eaa2e44/39421308291.pdfIn PDF document text
    • https://its-bulgaria.bg/files/file/81413312337.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/cea37a01d93a1202894d1cafaafc6465/37131663616.pdfIn PDF document text
    • https://reflexlighting.com/wp-content/plugins/super-forms/uploads/php/files/a6ee5bbb1f61d733b09e56fae8c701c5/bulabotot.pdfIn PDF document text
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/6725fdc721c935ba51fe9af1bc7ff148/teragu.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a07440a11b4---zurerimarabijidefusa.pdfIn PDF document text
    • https://simondaulte.com/ckfinder/userfiles/files/24040403394.pdfIn PDF document text
    • https://www.cukoyem.com.tr/wp-content/plugins/super-forms/uploads/php/files/3tc77k23tm2kbb9pdmhstv8100/47808116158.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=samira+league+of+legends+buildPDF link annotation
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/6ca45073d4bc6becdf11c526190209c0/lepujov.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df4a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF4A 5468 bytes
SHA-256: 31aedc95a1ec836b59ba50afb830315db27067032220d0fe8efb145da9a98948
font_01_sfnt_off0000f1c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1C4 12196 bytes
SHA-256: c5378e593529014ffde9febf587ebb9e22ea1f09686b7422f0f358410518cdcb