Malicious PDF — malware analysis report

Static analysis result for SHA-256 1ef8928df233724a…

MALICIOUS

PDF

88.4 KB Created: 2021-07-08 01:07:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: cdc8fd1ee8573e5b622783bec29d75d7 SHA-1: 5550fef2fcee67144b3ac837c3afc1a232e36352 SHA-256: 1ef8928df233724ad820ef9f6e6d72185418357e4647597ea98e6c44e8c050fc
156 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 compromised WordPress uploads or other disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 http://asdgolfclubtoscana.com/writable/public/userfiles/file/4817772067.pdf In PDF document text
    • http://bestforfishing.com/wp-content/plugins/super-forms/uploads/php/files/95a0ed5c4764cafca76462e6a3de50d8/xuxexaletuxonidodevemi.pdfIn PDF document text
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/1608b0833897be---23865786039.pdfIn PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1608ee7f176857---vevogetanagepozigekodi.pdfIn PDF document text
    • https://hzautomatisering.nl/userfiles/file/92754085404.pdfIn PDF document text
    • http://cloverpark1961.com/clients/6/6a/6a73a08bb68f643008adb5efbbb44e43/File/78548647230.pdfIn PDF document text
    • https://gradeagroup.com/wp-content/plugins/super-forms/uploads/php/files/4dcn0vcffce35o8hd032kae5ff/zaxuvijofe.pdfIn PDF document text
    • http://raunlarose.us/wp-content/plugins/formcraft/file-upload/server/content/files/16083c8645bb28---60412274245.pdfIn PDF document text
    • http://learningkey.org/userfiles/bawavabe.pdfIn PDF document text
    • https://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/916c5e22296e0871c499f4dded97a837/14683246501.pdfIn PDF document text
    • http://www.holderit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d3e4e5fed7---14824336268.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/160bd4e49126a7---fovaweperitemigufubemale.pdfIn PDF document text
    • http://anaminfo.com/attachfile/file/makejesububejaxuj.pdfIn PDF document text
    • http://hutbephottaihaiphong24h.com/upload/files/92021646776.pdfIn PDF document text
    • http://mellorymotors.ru/admin/ckfinder/userfiles/files/79061323972.pdfIn PDF document text
    • https://www.andyselfstorage.co.uk/wp-content/plugins/super-forms/uploads/php/files/0m73mc87b7n6dmu12ohr7j3aog/47628985108.pdfIn PDF document text
    • http://www.awakohchang.com/image/upload/File/oxazajasuripe.pdfIn PDF document text
    • http://capmar.eu/userfiles/file/21788664265.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b63577b4220---28702086143.pdfIn PDF document text
    • https://relaxationplusmn.com/wp-content/plugins/super-forms/uploads/php/files/b72b87afa41b32caf3790310c4b75b79/sifirin.pdfIn PDF document text
    • https://www.verpoort-bouw.be/wp-content/plugins/formcraft/file-upload/server/content/files/160791d1823635---nesuwane.pdfIn PDF document text
    • http://fertilityupdates.com/userfiles/files/43933640787.pdfIn PDF document text
    • http://renovfab-menuiserie.com/userfiles/file/felilirodakurerezibunab.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609185526e3dd---wazuveka.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=specific+heat+capacity+of+airPDF 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_off0000f7a6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7A6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010fb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FB8 17156 bytes
SHA-256: 7b64b0014f8ecd0d7280ea6ee470f3d29564c1cdab1e7a08cc048146985aefa4
font_02_sfnt_off00013c97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C97 10448 bytes
SHA-256: 664489462c0e4c0bfad9e8355b6655ea0f625a3eafde3461ed2c7d27f651901f