Malicious PDF — malware analysis report

Static analysis result for SHA-256 418a0bf267aab2e2…

MALICIOUS

PDF

87.6 KB Created: 2021-09-14 06:36:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: b4c1aa3f89c78f61f0fb56ce47fcdfe8 SHA-1: 40c46722a7049264c688d0bb61576834957e7411 SHA-256: 418a0bf267aab2e2304edbc8e261057fd5fe79505e3ca95774ca2c7e088aba80
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to various external URLs, some hosted on compromised CMS platforms. The presence of multiple PDF links and the 'utm_term' parameter in one URL suggest a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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://coretry.ru/uplcv?utm_term=tif+file+android PDF link annotation
    • http://cosonhuath.com/hinhanh_fckeditor/file/39948491363.pdfIn PDF document text
    • http://bigdoughpizza.com/uploads/files/19985778977.pdfIn PDF document text
    • https://heureka-cz.eu/files/tikaz.pdfIn PDF document text
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/9j32fnuhnnuph1uha8n44jc0e1/lijegebilenafexumotuluku.pdfIn PDF document text
    • http://townofwinslowin.com/flash/townofwinslowin.com/file/41617035418.pdfIn PDF document text
    • http://lungshingcentre.com/userfiles/68480507705.pdfIn PDF document text
    • http://victorylimo1.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a117daaac0---levapeguxotumatenuxi.pdfIn PDF document text
    • http://opuspoint.com/ckfinder/userfiles/files/fawexi.pdfIn PDF document text
    • https://vishalahospitality.com/ckfinder/userfiles/files/levapujifan.pdfIn PDF document text
    • http://zapatosperezcabrera.com/ckfinder/userfiles/files/gamurovuku.pdfIn PDF document text
    • https://educationindiajournal.org/ckfinder/userfiles/files/kinireluzizopilesobogagek.pdfIn PDF document text
    • http://dija.lv/public/userfiles/file/luxikamob.pdfIn PDF document text
    • http://zhihepvb.com/upload/ckimg/files/202109102335078563.pdfIn PDF document text
    • https://kemxoi.vn/app/webroot/files/images/pages/files/kariru.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1613b40ed1e6df---91409583283.pdfIn PDF document text
    • https://livnica-metalurg.com/images/pages/file/91417637923.pdfIn PDF document text
    • http://eventechsite.com/files/files/55915359212.pdfIn PDF document text
    • http://suchanekstomatolog.pl/files/file/91600516970.pdfIn PDF document text
    • https://studio45.live/wp-content/plugins/super-forms/uploads/php/files/2gu7usedpmrq1agnt9j67mtknd/14104399276.pdfIn PDF document text
    • https://vientangluc.com/upload/files/rewixuganituluwojodepi.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/161392872838a0.pdfIn PDF document text
    • http://chongqinghaohong.com/upload/files/kawikofas.pdfIn PDF document text
    • http://zovsh.com/Uploadfiles/files/rasajifikejotokinoz.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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_008_off000138ad.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x138AD 16528 bytes
SHA-256: df7555bab474353d8a4f07066b76af8d7980525922d178eb59c8296033c26aca
font_00_sfnt_off0000c759.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC759 22816 bytes
SHA-256: b351d7dc8899e881380bcdb80674a62882cab861bab6ce1cf86743537c789e4f
font_01_sfnt_off000101c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101C4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000119d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119D1 1820 bytes
SHA-256: ef4c56b83544acc0eae329b123dcb13384a4443b8ee25b6b011fcec9f25c534c
font_03_sfnt_off0001225c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1225C 10044 bytes
SHA-256: 6b6dc900620fc487368f699a0397824fe81e7afb4b9f2c961ed7c8a91e8150b7