Malicious PDF — malware analysis report

Static analysis result for SHA-256 76a6818f24aeb082…

MALICIOUS

PDF

81.3 KB Created: 2021-09-04 05:53:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 02f44b65dc9342b244ed47ba1fa8ac5e SHA-1: 0c1a56812a07d235d5dacaf301273ed3a63f3678 SHA-256: 76a6818f24aeb082ca6e99d9c308bee21c82f568196c6d27fc96aea0f1baa7ca
164 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, pointing to multiple compromised WordPress upload directories and disposable hosting sites, likely serving as a lure for users to download further malicious content. The presence of a visual download button heuristic further supports this phishing-like attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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
  • 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.
  • 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://www.marsagri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb375e1d673---56725605827.pdf In PDF document text
    • http://glovimex.com/uploads/ckfinder/files/77279710863.pdfIn PDF document text
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/72k06dso3lqk94cvdqgbofs4k7/59125976416.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac0e603399b---lekuwomedawid.pdfIn PDF document text
    • http://biotop-zamosc.pl/userfiles/file/47298424466.pdfIn PDF document text
    • http://trickorsuite.com/clients/5/5d/5d84d12f6f4dfd10bbe5497c884a5f3e/File/tijanarivogalepogunivaxij.pdfIn PDF document text
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/vmdie2q4q9699jnq02iibk1qo4/57380633543.pdfIn PDF document text
    • http://mas.vacations/wp-content/plugins/formcraft/file-upload/server/content/files/160706cfe1fd29---96574228244.pdfIn PDF document text
    • http://qachs88.com/clients/58271/File/gutafakul.pdfIn PDF document text
    • https://gfow.om/wp-content/plugins/super-forms/uploads/php/files/rlotvovm5gffjcgrgavqgb979c/41654782008.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1610308fb2a95a---sununobik.pdfIn PDF document text
    • http://unipell.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606d58526450b---borijazofifirozugatinux.pdfIn PDF document text
    • http://www.tsssport.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096e472895ee---9174608240.pdfIn PDF document text
    • http://www.training4thefuture.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607cd3593e446---71246949287.pdfIn PDF document text
    • https://stpeterscbs.ca/ckfinder/userfiles/files/32589509380.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/dab484c312727fe377e7322b45e12eae/99577577689.pdfIn PDF document text
    • http://sbkf.org/files/files/48779729582.pdfIn PDF document text
    • http://christopherdallo.com/file/37209751178.pdfIn PDF document text
    • http://minhanh.com/files/66871073750.pdfIn PDF document text
    • http://topup-fight.com/ckfinder/userfiles/files/42868179315.pdfIn PDF document text
    • https://bawwabatrizq.com/userfiles/file/jojaborepaxefewitewi.pdfIn PDF document text
    • https://horgaszvelem.hu/ckfinder/userfiles/files/80561166101.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/9dd71e819dea873797f51b65453d0e52/56704044008.pdfIn PDF document text
    • http://principessavencanice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9ec65e13c6---20818062693.pdfIn PDF document text
    • https://realestateconnect.biz/wp-content/plugins/super-forms/uploads/php/files/tnab1ugg1i378a15vq814sbvu6/vepexedanem.pdfIn PDF document text
    • https://roweryelectra.pl/app/webroot/uploads/file/16213244688506.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=english+worksheets+for+first+grade+pdfPDF 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_off0000d834.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD834 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f046.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF046 17780 bytes
SHA-256: d1c1f6b6a0762405ff277afd634be5353236b8ff9e085e5ee75bbbdb9e2f1706
font_02_sfnt_off00011e5d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E5D 10936 bytes
SHA-256: 1c3c5448b1bfa5621fe647f672d1150eaf42cb0b8ef6e86493feeccb0f3f5059