Malicious PDF — malware analysis report

Static analysis result for SHA-256 e541f906b2f6d054…

MALICIOUS

PDF

83.2 KB Created: 2021-07-13 19:25:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 85e492663022ce76bdcc51973bb26ad7 SHA-1: 821a74ea527c5ec6994325a89e6f8321d85c15e7 SHA-256: e541f906b2f6d0540d2b5cb9b5d86349367912710a1be0fe3e631ac2a02714c9
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting it's designed to redirect users to potentially harmful sites. No scripts were extracted, but the PDF structure and embedded URLs strongly suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9896

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.advokat.com/app/webroot/img/fck/file/17322047695.pdf In PDF document text
    • http://ngpsusa.com/wp-content/plugins/super-forms/uploads/php/files/121tr0l8ues9njeccni4lrjmo1/rexibuwakomepupoxusewu.pdfIn PDF document text
    • http://maxtarget.by/ckfinder/userfiles/files/9703049508.pdfIn PDF document text
    • https://cashcruis.ru/wp-content/plugins/super-forms/uploads/php/files/0ffb6dbbbffb675c8c417f09757eec39/19848861706.pdfIn PDF document text
    • http://orgue-chantepie.info/FCKeditor/upload/file/57345257121.pdfIn PDF document text
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/ba11d9f4befd4b6b8ad6dc07ea337d95/gojenajiwafolore.pdfIn PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071facf67652---9532450116.pdfIn PDF document text
    • http://blessingsngo.in/userfiles/files/93668106561.pdfIn PDF document text
    • http://mobydick-band.de/fckdata/file/xufixeruxuw.pdfIn PDF document text
    • http://duhochmis.com/files/uploaded/files/xudikovapakup.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1606d8a7c4a4d0---zevedugagaditetupi.pdfIn PDF document text
    • http://childconnect.com/swi/fckfiles//file/fomituwenubixedidoza.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607760e99b4e5---xezodefurox.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16085be01a5b79---bubozonexil.pdfIn PDF document text
    • https://www.superioreagle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e67370be7e---jotalitativanojifevofipu.pdfIn PDF document text
    • http://arch-teh.com/pic/userfile/59868099655.pdfIn PDF document text
    • http://minerva-collection.net/files/files/37377784308.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2ca65a917b---25577126601.pdfIn PDF document text
    • http://associacaoguainumbi.org.br/wp/wp-content/plugins/formcraft/file-upload/server/content/files/160940fa502ac8---zotukejofe.pdfIn PDF document text
    • https://rpdev.org/ckfinder/userfiles/files/buxiduz.pdfIn PDF document text
    • https://alternativecarrepair.com/userfiles/file/sukewudoz.pdfIn PDF document text
    • https://businesslife.com/content/file/92196591590.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=social+values+and+social+consciencePDF 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://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_off0000e832.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE832 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010049.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10049 10408 bytes
SHA-256: cea846dedd06a6c5521d5e07efc483c77a593e664b0f3761286d3d5c798d447f
font_02_sfnt_off000117eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117EB 17252 bytes
SHA-256: 4590a99ee8e3f009a5ea51530efdc2d5e7c274263cb53e88716dda070135c857