Malicious PDF — malware analysis report

Static analysis result for SHA-256 65b66d15900b3be8…

MALICIOUS

PDF

73.3 KB Created: 2021-09-09 18:43:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 2f7e01b9f257759feb5f6df4f2b4b47b SHA-1: 9106ba6167f4266e79f64c0afdc0d33aaae232d8 SHA-256: 65b66d15900b3be88f0d1ead09347bb427c1051bbf436a2c9595fd028fae5be2
126 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 domains hosting PDF files, suggesting a link farm designed to redirect users. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic and the high number of distinct, unknown reputation URLs support this. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://baocaosudanang24h.com/uploads/image/files/xekisikoserefaforomupi.pdf In PDF document text
    • http://www.klccpa.com/userfiles/file/In PDF document text
    • https://ldoris.com/upfile/files/20210904070802.pdfIn PDF document text
    • https://jurvamartin.com/userfiles/file/wokodasalukasofijiga.pdfIn PDF document text
    • https://mayxaydungthienlong.com/uploads/files/files/jediwo.pdfIn PDF document text
    • http://hamzalegalservices.com/userfiles/file/sonimozilanoxuze.pdfIn PDF document text
    • http://haisushitogo.com/uploads/files/vuzamijijujepafogazinet.pdfIn PDF document text
    • http://www.autoservis-hubatka.cz/admin/upload/ww/file/duwadodepoworasukufonel.pdfIn PDF document text
    • http://abogadosaguilar.com/ckfinder/userfiles/files/19823589582.pdfIn PDF document text
    • http://timnhanhonline.com/upload/files/wudolazukupipezapuwotek.pdfIn PDF document text
    • http://radecznica.pl/userfiles/file/jibivoko.pdfIn PDF document text
    • https://crmsaas.dswip.com/ci/userfiles/files/zumejulilukaxawalubuzus.pdfIn PDF document text
    • http://easyreturn.store/userfiles/file/jifewemu.pdfIn PDF document text
    • https://nailseasupportgroup.com/wp-content/plugins/super-forms/uploads/php/files/2449996c0df9d269da6d5f420557a8e4/woxurawijikavo.pdfIn PDF document text
    • http://nsdadventist.org/FCKData/file/36962034330.pdfIn PDF document text
    • http://symbolfoods.com/files/file///liridudisixaketeradimo.pdfIn PDF document text
    • http://cjcounsel.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/bosusivojefotiwixajugizak.pdfIn PDF document text
    • http://officegate.biz/admin/fck_upload/file/75882147838.pdfIn PDF document text
    • https://www.colline-eternelle.com/ckfinder/userfiles/files/38935558584.pdfIn PDF document text
    • https://ropaalmayoreo.com/images/userfiles/file/61292594246.pdfIn PDF document text
    • https://www.techsrollout.com/wp-content/plugins/formcraft/file-upload/server/content/files/161319e4395344---56263791241.pdfIn PDF document text
    • http://clarklawtexas.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/45572640626.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=3+composite+numbersPDF 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_off0000bb06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB06 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d31d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD31D 10640 bytes
SHA-256: d0bd1cdba636d5371baa41f725407b211d95a2da34a9e459aeff567f24788fff
font_02_sfnt_off0000eb37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB37 17436 bytes
SHA-256: 76d556bf04f5ad74b8ac4fd926db264e8de54dfeaf284ad26495d24efcddd592