Malicious PDF — malware analysis report

Static analysis result for SHA-256 e805350b17604cb0…

MALICIOUS

PDF

70.2 KB Created: 2021-09-25 03:52:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: a82583e06e108b37008258246390de40 SHA-1: 5b714c7e8093534c945ad3d5c512be1609edfa24 SHA-256: e805350b17604cb0e6440084390230fe99daed3345c747ee385c4fa97cfa8d89
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains a large number of embedded URLs, many of which point to compromised CMS upload directories or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with a malicious link farm designed to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://nomylo.ru/uplcv?utm_term=popular+apk+games PDF link annotation
    • http://nb-magnet.com/upload/files/12356287320.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/db4f22402ffc2ede4dd749ecf2d733b6/dujoxi.pdfIn PDF document text
    • https://braindevelopmentmaps.org/userfiles/files/89305217350.pdfIn PDF document text
    • http://80tner.friend-match.com/upload/files/xijafidepigago.pdfIn PDF document text
    • http://avvocatogiuliani.it/userfiles/files/76729470406.pdfIn PDF document text
    • https://on-call-anatomist.org/ckfinder/userfiles/files/37379507153.pdfIn PDF document text
    • http://www.gulbaharsigorta.com/contentData/file/rudukebikixeravalij.pdfIn PDF document text
    • https://kimcert.com/E/file/49277062863.pdfIn PDF document text
    • http://marketingnews.fr/images/file/tudalufazudekerexuruxeb.pdfIn PDF document text
    • https://zlato-stribro-investice.com/upload/files/ronitejetebivevaduxosamo.pdfIn PDF document text
    • http://training-solutions.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613478618a6c9---58205894503.pdfIn PDF document text
    • http://www.luna1956.com/images/library/File/69326213998.pdfIn PDF document text
    • http://thepnguyentran.com/media/ftp/file/ditidelifamivikamiramuja.pdfIn PDF document text
    • http://aquaclub.hu/userfiles/file/jezegutotozanos.pdfIn PDF document text
    • http://camel-republic.com/media/userfiles/files/kemume.pdfIn PDF document text
    • https://learningsolution.ca/userfiles/files/45045224845.pdfIn PDF document text
    • http://hausdergesundheit.net/userfiles/files/daminogurazufuxizo.pdfIn PDF document text
    • https://weingut-suppan.at/files/78818675455.pdfIn PDF document text
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/f3652d8d8b404cc44c01f830b7ef21ae/24062729922.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/16141eb60c81be---26472599662.pdfIn PDF document text
    • http://j-club.eu/userfiles/file/buwuwugukaratazesupuzu.pdfIn PDF document text
    • http://lexxyin.net/files/fckeditor/file/67334130916.pdfIn PDF document text
    • http://zabradli-znerezu.cz/userfiles/file/vuwurozoripumitaxabalogiv.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://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_off0000b05b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB05B 10496 bytes
SHA-256: c94f39b76fb0386c202af795023890df8f3fc8e10f0c7c2673f0594453c73c4b
font_01_sfnt_off0000c84c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC84C 17124 bytes
SHA-256: fc98a7888ab9af5b61ef23f068a35944ba9a197970667c2bbc4add0b6e002262
font_02_sfnt_off0000f3db.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3DB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1