Malicious PDF — malware analysis report

Static analysis result for SHA-256 c78db0a9470e30c8…

MALICIOUS

PDF

86.5 KB Created: 2021-07-16 14:21:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: ca62083a09f011dd82c76f5ea0de6021 SHA-1: 90e4fcdc93e0c3e51d7b038b3f938216c5dc6cab SHA-256: c78db0a9470e30c8e332dc05dffcf4dd98767f562fb300e48750a5eb172d7fd5
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous embedded URLs that point to compromised WordPress sites, suggesting a link farm designed to redirect users to potentially malicious content or phishing pages. The ML classifier strongly indicated maliciousness, and the presence of multiple distinct hosts hosting PDF files via vulnerable plugins supports this assessment. No scripts were extracted, but the URL structure implies a phishing or content-luring attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • 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://queure.ru/uplcv?utm_term=what+is+your+biggest+failure+example+answer+for+freshers PDF link annotation
    • http://www.auditsi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf10496f144---95363679831.pdfIn PDF document text
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d5dbcccfbf7---69652948701.pdfIn PDF document text
    • https://canadiancontractorservices.com/wp-content/plugins/super-forms/uploads/php/files/4qs04js2jjl4skhlecn94b4of2/guweninelujobu.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/09ded373b7c3d0da05fea646a6f83f2e/sakujadug.pdfIn PDF document text
    • https://nwdglobal.com/ckfinder/userfiles/files/nenegarozunurotufa.pdfIn PDF document text
    • https://funkydrop.shop/wp-content/plugins/super-forms/uploads/php/files/4b8e16593544f7a2567f4d3e3a84da0f/74800899586.pdfIn PDF document text
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b6c43abf894---wuwum.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1606d8b622fe5d---71253285081.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088829a58ac6---46440405486.pdfIn PDF document text
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c6ca6b4825---94817461607.pdfIn PDF document text
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/41380408212a7e322506c21755df537e/xuren.pdfIn PDF document text
    • https://thetitangroup.ca/wp-content/plugins/super-forms/uploads/php/files/5713798c65dc101e4f271e2d3e69927e/nuduwo.pdfIn PDF document text
    • http://simonide.org/userfiles/file/patuloputipafatinapesipa.pdfIn PDF document text
    • http://eko-inwest.eu/upload/file/92604991024.pdfIn PDF document text
    • http://paramountswimwear.com/userfiles/files/viromowukemenasos.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/8euul772elpca36gbb5mingn34/99227268068.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609c97a40b574---67440490802.pdfIn PDF document text
    • http://www.saito-ken.jp/userdata/file/fenuruledonisixoka.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_off0000f01f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF01F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010831.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10831 16296 bytes
SHA-256: fd33fa247793fb5712a733d0ca1f44dcb32c8c5ebf2982e87f6cec22791139bb
font_02_sfnt_off00013247.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13247 11340 bytes
SHA-256: 7aac1cecac8a412cba8715d2559f469e3b19fd9dcfbd6220a6cf3a0ef84402c8