Malicious PDF — malware analysis report

Static analysis result for SHA-256 7635487705f2bd5f…

MALICIOUS

PDF

87.7 KB Created: 2021-07-07 01:01:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 508a0ad14c132b84aaa8abc925cf7c8a SHA-1: 4275b7a73dba406093b8125fb48e9ea19440badf SHA-256: 7635487705f2bd5f3ee3cd22e31faa72468cc49289e81c469bee6ad6f63e9a0a
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to compromised websites, identified as a link farm. Heuristics indicate these links are hosted on potentially disposable or compromised CMS upload storage, suggesting a distribution mechanism for malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607498a529880---watomubejijurafelutolexi.pdf In PDF document text
    • https://studiogreenwich.ru/wp-content/plugins/super-forms/uploads/php/files/c60128ac2faa8f6e4bfecc5718e59a9c/kuduvizosi.pdfIn PDF document text
    • http://brothersaluminium.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/16081346809254---33741209957.pdfIn PDF document text
    • http://magicdiscoradio.hu/userfiles/file/11966248939.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb8af299998---13009363124.pdfIn PDF document text
    • https://szabobuszberles.hu/files/files/90320203132.pdfIn PDF document text
    • http://www.mywil.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160b005503adb0---51394119998.pdfIn PDF document text
    • https://www.qlsny.com/wp-content/plugins/super-forms/uploads/php/files/5f642eb5d242c9eba6ddff81532537a6/palorejewunojezuregipuwe.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c345eadd82f---57214797396.pdfIn PDF document text
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/9507ced0848dd9e885c9cbbdb01b65fa/zijixojepejot.pdfIn PDF document text
    • http://cuatudongbinhduong.net/uploads/files/79350791579.pdfIn PDF document text
    • https://zebcom.in/userfiles/file/60766905323.pdfIn PDF document text
    • http://gorisum.net/fckeditor/upload_file/file/xusulo.pdfIn PDF document text
    • https://northstarexecutivesearch.com/wp-content/plugins/super-forms/uploads/php/files/c78dcb26e2c33a4bda1c60a7c84fd504/puxatoj.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607be5d54a70e---42242156615.pdfIn PDF document text
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160898f3652a06---71841004389.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2f5a74a78f---28678397591.pdfIn PDF document text
    • https://www.mysmilestudios.com/wp-content/plugins/super-forms/uploads/php/files/b0bb6cc6dc500aae9ba5b57cbb1e49fb/93612374097.pdfIn PDF document text
    • https://www.cocochan.com.pk/wp-content/plugins/super-forms/uploads/php/files/5557c28ca7dfc886fd6c6d7a6581c90d/rajijuto.pdfIn PDF document text
    • http://ruoumoc.com/upload/files/11077622808.pdfIn PDF document text
    • https://infrastone.com/userfiles/files/40352253670.pdfIn PDF document text
    • https://chetanaus.org/bheru/uploadfiles/file/nabez.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/03tp8p6p74ir417l3tm6plesdj/47633014331.pdfIn PDF document text
    • http://riskhedgetech.com/uploaded/file/10720544666097c102141da.pdfIn PDF document text
    • https://ilc.ua/wp-content/plugins/super-forms/uploads/php/files/nsq7gh9kmbf4bq3g7um93ndeb7/77513003660.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=scooby+doo+2+sinhala+full+movie+free+downloadPDF 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_off0000f293.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF293 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010aaa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AAA 11344 bytes
SHA-256: 9e53ec019bb6235d72fcb04de53f11ffd3bfe847a0ed14cf7c331147fd18288b
font_02_sfnt_off00012533.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12533 16808 bytes
SHA-256: 99c96d9a82ca61512f8d086b4bbe707e32e0558beae970e538c847b8d7bf4943