Malicious PDF — malware analysis report

Static analysis result for SHA-256 6d18e41749e5c6e9…

MALICIOUS

PDF

81.6 KB Created: 2021-09-05 06:47:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 531eccc8fc9321a96678b5f3e104ca65 SHA-1: bb31d9bdc3d70c86e02fb017eba9923aef25768d SHA-256: 6d18e41749e5c6e91fe377efef79a4ec6123e45307b06dd3e2340c3c81a9c362
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URL analysis point towards a malicious document, potentially leveraging embedded JavaScript for exploitation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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://chambredhotes-savoie.com/ckfinder/userfiles/files/tufaw.pdf In PDF document text
    • http://allmedicus.com/userfiles/file/nodanevezefenavibezeruwo.pdfIn PDF document text
    • http://gaskinfamilyreunion.com/clients/b/b7/b798c9f9e2af69c3a5b950a06e4ade8e/File/24040633421.pdfIn PDF document text
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cbb99d4a34---xalaludek.pdfIn PDF document text
    • http://extrastyle.ee/ckfinder/userfiles/files/jikamaxot.pdfIn PDF document text
    • http://keralastatetailorsassociation.com/userfiles/file/potuwivemikepubug.pdfIn PDF document text
    • https://sharjahcements.com/images/bulk_images/files/64242467881.pdfIn PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/59f5045f04c7e64263847e8c2474e789/45612759022.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8649fdab16---xalexirezuratu.pdfIn PDF document text
    • http://elisa5888.com/shopadmin/upload/files/90626871965.pdfIn PDF document text
    • http://math-talk.kr/wp-content/plugins/super-forms/uploads/php/files/525bnjhn2mbviobt0uh4i63abl/53662781357.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/160833d764af9f---tabuveli.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071ee429b7ec---revaki.pdfIn PDF document text
    • http://doktor-okonski.pl/uploadimg/file/zepuwu.pdfIn PDF document text
    • https://esprimagroup.com/userfiles/file/6969335169.pdfIn PDF document text
    • http://gwtcs.org/Content/uploads/files/68591260563.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f9f5571c40---burumitifol.pdfIn PDF document text
    • https://bechtoldpaving.com/wp-content/plugins/super-forms/uploads/php/files/9662eecfecedecdf6459ecc039e8c2d1/bokifidofekujivupepubipen.pdfIn PDF document text
    • http://astro2sphere.com/admin/images/file/volizofemarerorelafirejat.pdfIn PDF document text
    • http://sevenseahotel.com/uploads/images/files/pusuneridoge.pdfIn PDF document text
    • https://www.partyshuttlebus.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609431f090ded---xojowox.pdfIn PDF document text
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16114838e7c0b5---mosorezixerixupifa.pdfIn PDF document text
    • http://cofetariafraguta.ro/UserFiles/file/85075603496.pdfIn PDF document text
    • https://music-group-store.com/upload/files/mivizijorazanijif.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=1st+grade+math+practice+workbook+pdfPDF 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_off0000d8df.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8DF 17856 bytes
SHA-256: 1089522b445df36660785ff61c405e50ecda6c814e873a9e8727b6e2d663e427
font_01_sfnt_off00010732.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10732 11192 bytes
SHA-256: a39e785531dd071d91e4ee44290603ec48a791b93cd0e23479991eae8d40090b
font_02_sfnt_off00012114.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12114 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1