Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4efbf25604f798e…

MALICIOUS

PDF

77.5 KB Created: 2021-09-15 21:02:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: f2fc4bae825c80aae2789d940bdcc864 SHA-1: 4a243e4bc1b91f05ada6ddf393948e1683000d8d SHA-256: a4efbf25604f798ea9bfb87fb03041c15644bdc7b4ea4f1cf1378a29194b2ad8
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and multiple external links, many of which point to disposable hosting or compromised CMS upload directories. The presence of a visual download button lure, combined with the ML classifier and ClamAV detection, strongly indicates a phishing or malware distribution attempt. The embedded JavaScript likely facilitates the download and execution of a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 8

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://smidgel.ru/uplcv?utm_term=upx+browser+premium+apk PDF link annotation
    • https://acp-luxusingatlanok.hu/ckfinder/userfiles/files/dewutazorivifib.pdfIn PDF document text
    • https://daaeportrett.no/upload/file/bukup.pdfIn PDF document text
    • https://unosms.us/userfiles/file/saloserevekejiwofuwubidew.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16141e1490d62e---xoxesufubufixun.pdfIn PDF document text
    • http://elsped.hu/files/file/47488720927.pdfIn PDF document text
    • http://faw-asia.com/image/upload/files/1961709278.pdfIn PDF document text
    • http://bkm-market.net/userfiles/file/fanuwolojosoxox.pdfIn PDF document text
    • http://hwangtosidae.com/userData/ebizro_board/file/9114581922.pdfIn PDF document text
    • http://www.chp.pl/ckfinder/userfiles/files/lezojod.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141cfc44a5a9---14841871495.pdfIn PDF document text
    • https://gornjastubica.hr/files/sobosozivozasi.pdfIn PDF document text
    • https://empezo.xyz/js/ckfinder/userfiles/files/ritagutewuzolabiwu.pdfIn PDF document text
    • http://cartonwrappingmachine.com/userfiles/file/14725359763.pdfIn PDF document text
    • https://telorgabus.com/contents/files/kajuvemigif.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132c91fdde85---86748266352.pdfIn PDF document text
    • http://www.beautyvogue.ch/Files/file/vipex.pdfIn PDF document text
    • https://lockerova.eu/admin/upload/documents/kegodigunotutafan.pdfIn PDF document text
    • http://gzky.cn/dubeite/ckfinder/userfiles/files/20210902_085058.pdfIn PDF document text
    • http://iuf.kr/pds_down/files/xojorubozi.pdfIn PDF document text
    • http://oumkua.com/userfiles/file/kobunojumug.pdfIn PDF document text
    • https://maharajganjtimes.com/assets/ckfinder/core/connector/php/uploads/files/73792057483.pdfIn PDF document text
    • https://dptech.vn/uploads/files/62351307819.pdfIn PDF document text
    • http://terezmisszio.eu/files/file/japefabadoxiforuzonuseb.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_off0000c8ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8AD 10692 bytes
SHA-256: ec012e5b5f17682e7c00a6f4fdd274046ef14b7fd8ab565c0d85c80406447988
font_01_sfnt_off0000e113.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE113 18144 bytes
SHA-256: f57e59d54d41ba44c4210d8a4c5d388f69883ac913580b33649f4da01eaf160c
font_02_sfnt_off000110b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110B3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.