Malicious PDF — malware analysis report

Static analysis result for SHA-256 1acfecfa51eff81e…

MALICIOUS

PDF

80.2 KB Created: 2021-09-11 12:12:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 9f05091e0558d131d666a7e7cd058a09 SHA-1: ea984667f72ea48c81c0fae89c0b3b57fb532867 SHA-256: 1acfecfa51eff81ea2c9071fe6c19b61fc80fc476160dd6cc00504e92466502b
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, many of which point to suspicious domains and are likely part of a link farm. The presence of a 'download button' heuristic further suggests a malicious workflow aimed at tricking the user into downloading a payload. ClamAV detection and ML classification strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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 http://tieulongcopro.com/luutru/files/gidililezuzisazitomemep.pdf In PDF document text
    • http://utcsp.rustyramone.com/uploads/files/fepunozulewili.pdfIn PDF document text
    • http://timnhanhonline.vn/upload/files/17464004322.pdfIn PDF document text
    • http://modernplating.com/userfiles/file/23150200313.pdfIn PDF document text
    • http://linhkienhunganh.vn/luutru/files/muriwomazapomoxixunaxo.pdfIn PDF document text
    • http://studioguagnoni.it/userfiles/files/nufamubipat.pdfIn PDF document text
    • http://volvo-cars.jp/js/upload/files/56776674299.pdfIn PDF document text
    • http://intertribo.sk/files/77436752531.pdfIn PDF document text
    • http://balcimimarlik.com/resimler/files/jomosolilas.pdfIn PDF document text
    • http://vinhthuanvietnam.com/upload/files/rozefexekadibanabawe.pdfIn PDF document text
    • https://tims.ro/ckfinder/userfiles/files/79820029944.pdfIn PDF document text
    • http://bekescsaba.varosom.hu/userfiles/files/25879449012.pdfIn PDF document text
    • http://www.maderas-navarro.com/ckfinder/userfiles/files/getigadonuzimibewe.pdfIn PDF document text
    • https://lazerom.pro/media/file/92439916484.pdfIn PDF document text
    • http://alrabbancapital.com/file/files/kuwas.pdfIn PDF document text
    • https://www.brunosistemi.com/wp-content/plugins/formcraft/file-upload/server/content/files/161309330ee18e---kamevasarexafiwotujajo.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/16139c69a3a431---73379683725.pdfIn PDF document text
    • https://joebalogh.ro/imagini_ws/faliximigili.pdfIn PDF document text
    • http://pushgroup.lv/userfiles/files/74391455583.pdfIn PDF document text
    • http://numismatika-nbkpdy.cz/userfiles/file/83263303470.pdfIn PDF document text
    • http://zdravi-kromeriz.cz/files/file/gajurapalipapasegigani.pdfIn PDF document text
    • https://tenshinorchids.com/FCKeditor_upload/file/88906350752.pdfIn PDF document text
    • http://grabnerestriche.at/guwaz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=tubemate+video+mp3+converterPDF 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_off0000d688.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD688 10904 bytes
SHA-256: 84edf020f984c3b6320c294accf599da4ee42d9f2f73c1bec0c336670e84896f
font_01_sfnt_off0000ef89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF89 16820 bytes
SHA-256: 90f8e1d601268696faeed5cce662a911495615e218287bd54e72a2c8aaea7563
font_02_sfnt_off00011af8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11AF8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1