Malicious PDF — malware analysis report

Static analysis result for SHA-256 c36b1b3b548e6072…

MALICIOUS

PDF

222.2 KB Created: 2021-06-11 19:06:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: e35e79be92df5109fbfefc5ef33d7400 SHA-1: b7489f8edc9993d2bec109c34fa6da7669685980 SHA-256: c36b1b3b548e60727b186db0f4feb6c265849c5205eae38c10308cd4c454f099
194 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, with heuristics indicating it's a phishing lure requesting recovery secrets. The document contains external URIs and links to compromised CMS uploads, suggesting it's designed to trick users into downloading further malicious content. The presence of multiple compromised upload links and a direct link to a PDF on a compromised WordPress site reinforces the phishing and download lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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
  • Recovery secret / private key request critical SE_SECRET_RECOVERY_LURE
    Document requests recovery phrases, private keys, backup codes, or saved passwords. Requests for these secrets in a document are high-risk.
  • 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.
  • 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://irlanc.ru/uplcv?utm_term=spark+in+action+2nd+edition+pdf+free+download PDF link annotation
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8c1668355c---92507404462.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bce382e92c6---nojopuxewe.pdfIn PDF document text
    • http://fashioncenterpoint.com/wp-content/plugins/super-forms/uploads/php/files/cd0d41a630ff6d25d211e8d0990b399a/narutufudes.pdfIn PDF document text
    • http://monkey-do.net/userfiles/file/zibadusidofukujezidegebis.pdfIn PDF document text
    • https://olivier-daulte.com/ckfinder/userfiles/files/puguzelededogujedap.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607ee61e3d1d6---jumomavapipetixufajabinaj.pdfIn PDF document text
    • http://fitviewer.biz/files/file/wijizenafivujifetone.pdfIn PDF document text
    • http://uniroll.pl/user_images/file/30885120882.pdfIn PDF document text
    • http://ahkjt.com/upfile/file/23553976525.pdfIn PDF document text
    • https://isleo.com/i_photos/file/46398033672.pdfIn PDF document text
    • https://rsun.pro/admin/ckfinder/userfiles/files/60700586647.pdfIn PDF document text
    • http://asianaccounting.com/admin/fckeditor/userfiles/file/tavavusipufutakalatoro.pdfIn PDF document text
    • http://amazingindiaphotos.com/amazingindiaphotos//upload/fckimage/file/64147500936.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/djkmc46g38o7g5hljoujtbftfk/62795747915.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097cf8c70ef6---83588641361.pdfIn PDF document text
    • http://spoanalyze.com/wp-content/plugins/super-forms/uploads/php/files/7b0563d032b0f2a8160853992fd31849/litarivova.pdfIn PDF document text
    • http://fontawesome.iohttp://fontawesome.io/license/In PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00030774.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x30774 1696 bytes
SHA-256: 9c49f12e3410d4797e050638c3dc3bc5b54da7d6011bda4814ccc5cd6f6c91b4
font_01_sfnt_off00030fe0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x30FE0 5364 bytes
SHA-256: 433ca09df6b079d2cfc0d51640f566945dec4e0919e26740c69f75f8d17a53dc
font_02_sfnt_off00032246.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x32246 14844 bytes
SHA-256: 19fa4a91a9d42f4ffaa5a4666fd6b83bbae301d412a21e3b7b074ab9e8d54fe3
font_03_sfnt_off00035358.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x35358 16120 bytes
SHA-256: b8fa99db91b4e2a38fb01ca4f8dfd1970d271bfdaf7323161a8b02e369b8fc98