Malicious PDF — malware analysis report

Static analysis result for SHA-256 1631b9ac0c1ed43d…

MALICIOUS

PDF

77.6 KB Created: 2021-06-17 11:57:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 51ae0e08e58bfcac74b58c26f85e0e24 SHA-1: f06ea846da2c06d5ca06945f15edf30ba43d31d5 SHA-256: 1631b9ac0c1ed43d115b5a8f92ecdd68c72e1ec86a678beeec111a5b68bd5eb3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file is a PDF containing numerous links to external websites, many of which appear to be hosted on compromised WordPress installations or disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded URLs suggest the primary function is to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://synerhu.ru/uplcv?utm_term=individual+differences+in+second+language+learning+pdf PDF link annotation
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/74d850efca6b09801caba961d678062f/52494442728.pdfIn PDF document text
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b733fe7ad93---kigezazebof.pdfIn PDF document text
    • https://mattress-leader.com/media/62896128262.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a68613a5078---55486736696.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073830f77891---30063848515.pdfIn PDF document text
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/3mvr14nk97bqqggb0r7f1biln8/95599247028.pdfIn PDF document text
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/9814b40c7ffc98902341b59f7bdd0c58/72035836821.pdfIn PDF document text
    • https://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/t2jg8p2h4gco28si5ekrlpspl0/nesobew.pdfIn PDF document text
    • http://mega.kz/media/upload/files/sudikogozo.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ba126430c4---652014858.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/8160319393af779b62eb0b1a348aff65/wokiwosamipo.pdfIn PDF document text
    • http://kantoromega.pl/userfiles/file/gatotidebiwikuluxitamaxa.pdfIn PDF document text
    • https://space1500.com/wp-content/plugins/super-forms/uploads/php/files/bd54dfef6b1a2778374f349c1e148051/menatuzejimowezu.pdfIn PDF document text
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/na4ndudgsu6tdlgg840kr28ud6/24939025827.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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_off0000f0e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0E3 5320 bytes
SHA-256: 59b9510f12bcc8f4b35c1a4f5e9d4ab139f239ea1119dd112907d28ad6ccd5fe
font_01_sfnt_off00010318.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10318 11336 bytes
SHA-256: 4b009ace7f0a7e8ee038d44949bf6de3753b0ca36c9a5517cad1cb3fc6475058

Open this report in the interactive analyzer, or submit your own file for analysis.