Malicious PDF — malware analysis report

Static analysis result for SHA-256 45add66aa29f0bb3…

MALICIOUS

PDF

78.7 KB Created: 2021-09-08 15:27:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 9f69e68c51c0f918b479491a6a8aeba3 SHA-1: af8a1cdd4824804f5dad6f2c3dfaafba2c1ecb1a SHA-256: 45add66aa29f0bb3ce3e68f8d82e22cd6d5e7dcfac429df803947dfc349c4ee2
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to other PDF files hosted on various domains. Several heuristics indicate this is a link farm, with some links pointing to compromised CMS upload storage. The ML classifier strongly flagged this PDF as malicious, suggesting it's part of a larger malicious operation, potentially for SEO abuse or to distribute further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 5

  • 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://didaconcept.com/admin/fckeditor/file/jowuwevuxexu.pdf In PDF document text
    • http://swvocal.com/data/se2/file/89008361448.pdfIn PDF document text
    • http://solarexperte.ch/fckeditor/editor/images/file/38383266344.pdfIn PDF document text
    • http://phongthuyphatloc.com/luutru/files/xudamopejine.pdfIn PDF document text
    • http://ehoron21.mn/uploads/files/66886303540.pdfIn PDF document text
    • http://adhdesign.de/userContent/files/20210901002633-mobiputevivowekag.pdfIn PDF document text
    • http://kaitosushisb.com/uploads/files/kujezogipagalipoxabaxej.pdfIn PDF document text
    • https://maintogelonline.bet/contents/files/47909461039.pdfIn PDF document text
    • https://powermailer.in/userfiles/file/nudufufuwufoju.pdfIn PDF document text
    • http://szintai.hu/ckfinder/userfiles/files/dewilalotipojog.pdfIn PDF document text
    • http://gespk.com/userfiles/file/52546925268.pdfIn PDF document text
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/5084b3ba9c074881895681251ba4b066/72605741093.pdfIn PDF document text
    • https://betenrealestate.com/sites/default/files/file/78958924359.pdfIn PDF document text
    • http://greatwalledmond.com/ckfinder/userfiles/files/wejetafasen.pdfIn PDF document text
    • http://aaronandanthony.com/userfiles/files/mesatunaxosadizukip.pdfIn PDF document text
    • https://omnistopbollards.com/application/third_party/ckfinder/userfiles/files/12479324146.pdfIn PDF document text
    • http://studioghittigargnano.com/userfiles/files/rusegufetokiro.pdfIn PDF document text
    • https://ethnicminorities.heephong.org/ethnicminorities/cmsadmin/ckfinder/files/35388486470.pdfIn PDF document text
    • https://textosolutionslinguistiques.com/upload/editor/file/45109500688.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130d11a5f21d---gijametenuk.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/6757798064.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/m9ns3s8in59plf0520n06pm1e6/valesasadoketiridure.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=manual+tester+jobs+in+bangalorePDF 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_off0000ca25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA25 18940 bytes
SHA-256: 87842aa62d61ff51a2f1f1b6ea80ddb4b44404ad2b069ad66fb770b02c2a574d
font_01_sfnt_off0000fc51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC51 10648 bytes
SHA-256: 40cf29abad2aa277f7a102063be2c75060798a224849f938eb4c16ae6d468889
font_02_sfnt_off000114ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114CE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1