Malicious PDF — malware analysis report

Static analysis result for SHA-256 839222d33523ae0e…

MALICIOUS

PDF

79.2 KB Created: 2021-09-23 17:02:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 4418725d16974b7cf0d1e591dd1d2c4c SHA-1: ea9ff6d06f292124bbef8e355248232ca175f462 SHA-256: 839222d33523ae0ea652ab4c90706b731db59a7d06ccd0e564fb9637aac22485
156 Risk Score

Malware Insights

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

This PDF was flagged by ClamAV as a phishing trojan and by an ML classifier as malicious. It contains numerous embedded URLs, many pointing to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The presence of these links suggests an attempt to lure victims to malicious sites for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://keyflounge.nl/userfiles/file/lewulubikoki.pdf In PDF document text
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/5a60b3ce3411aa162f2a4f2230112ac1/29331858188.pdfIn PDF document text
    • http://hangquangauto.com/files/ladumezixaze.pdfIn PDF document text
    • https://marblo.com/app/webroot/img/files/6666732431.pdfIn PDF document text
    • http://kaitianjinghua.cn/admin/userfiles/file/202109181617094765.pdfIn PDF document text
    • http://gcoekmr.org/cukashmir/User_Files/imagefile/pewudo.pdfIn PDF document text
    • http://propertiesforrent.com/userfiles/file///rabalisazupok.pdfIn PDF document text
    • https://giaynangchieucao.com/userfiles/file/jojeralesipegavozujabisur.pdfIn PDF document text
    • https://vatlieutaphu.com/upload/files/zoxofarokivaboganutinefu.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144dbca6a609---59277271967.pdfIn PDF document text
    • http://xn--80aaaaaikdebj9ccf1ayja1b5a3q.xn--p1ai/ckfinder/userfiles/files/67580624732.pdfIn PDF document text
    • http://enewind.com/pliki/file/sixonulitubiva.pdfIn PDF document text
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/d57192340580b162b594f4ea11ae6e17/75273134466.pdfIn PDF document text
    • https://giriconsultancy.com/content_files/files/loledapaligewufalopisibel.pdfIn PDF document text
    • http://www.jamesbgriffinlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134dcff2ae8c---voxololojexuroze.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1613a21868f7fb---1463498704.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1613f78fb0af00---dukepigepixosow.pdfIn PDF document text
    • http://sity-luxe.ru/userfiles/file/94694553342.pdfIn PDF document text
    • http://marktoby.com/akram/know_news/admin/userfiles/file/nimadesikifafabebus.pdfIn PDF document text
    • http://casaledellasignora.it/userfiles/files/galinulobon.pdfIn PDF document text
    • http://ccswcd.com/userfiles/file/tusojudek.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=apk+clear+cachePDF 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_off0000d262.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD262 17672 bytes
SHA-256: 308a80544b3355e8396abf3c393a32710eca42fb666de3ecf0e835a5c3796ef9
font_01_sfnt_off000100ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100EE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011904.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11904 9960 bytes
SHA-256: 6527ec5e0e41cf0d5f9a2c66745efc044638af5cdef6b1f946850c370a7d3927