Malicious PDF — malware analysis report

Static analysis result for SHA-256 ff7f6407000d9f26…

MALICIOUS

PDF

88.4 KB Created: 2021-06-28 13:59:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 81e0229bae498c98b9498bc9015eebf8 SHA-1: 41cdf7c5b49939c9921b0d5bee95cdb2c338b369 SHA-256: ff7f6407000d9f26ed96e4086a1d2533babfbe5a100e239ee6dde6f2d2b79548
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to compromised WordPress upload storage and disposable hosting, suggesting a link farm designed to redirect users. While no scripts were directly extracted, the PDF structure and embedded URLs are indicative of a phishing or malware distribution campaign, likely initiated via spearphishing.

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 https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/36d3aa72a89779e2b5ae531d4edc96a0/rerujub.pdf
    • https://btegypt.comfile/82105368622.pdf
    • http://adamlegal.com/userfiles/file/65983536412.pdf
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1609cdcaf73f67---18435478785.pdf
    • http://naphogacomposite.com/upload/files/besabixi.pdf
    • https://elicopter-de-inchiriat.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609219cb3a0e5---xozem.pdf
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c14448a7eb1---65960417581.pdf
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/klus2ahhsootoeplt2abop5qb3/fapowajakexawilifozokuwe.pdf
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d178628df1---75810298589.pdf
    • http://immodraft.nrw/images/architekten_agentur_images_/file/gubixewi.pdf
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1609275094c5da---sedubemikuzodajiz.pdf
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dd2caba6f7---64260018464.pdf
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608197fa464bd---65228167601.pdf
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160c5152d0b106---pulakirineliwe.pdf
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/d30109ab72ff90e4d32f5969b1edeca2/55786465178.pdf
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9956b9da72---vodokupoxulito.pdf
    • https://stagerightstaging.com/wp-content/plugins/super-forms/uploads/php/files/e7719b445d0fe8ecb46f78fe1c4d98e4/zabozejap.pdf
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a96dfb6c5b9---82379523416.pdf
    • https://aihr-iadh.org/uploads/FCK_files/file/86884034222.pdf
    • http://jucal.es/images/file/29475508649.pdf
    • http://septumdent.com/img/userfiles/files/85893978634.pdf
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/2487b5b8961e092f68c278a53fc0d6a5/43484262983.pdf
    • http://jkmdc.com/aversystem.com/userfiles/file/22338569725.pdf
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607309a8d9a35---79628021249.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=construction+project+manager+resume
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f367.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF367 16792 bytes
font_01_sfnt_off00010b79.bin
1bb3899abf2469057cce43334cf5bf996891728b943267ee7bfdd2ace24440e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B79 17552 bytes
font_02_sfnt_off0001393f.bin
1d358b5439b09e24f474d7dde33bbb34d280caab98268b84b7c7f6d7a1360909
pdf-font-stream PDF embedded font (sfnt) at offset 0x1393F 10932 bytes