Malicious PDF — malware analysis report

Static analysis result for SHA-256 a676d135375febf3…

MALICIOUS

PDF

79.8 KB Created: 2021-06-24 09:31:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: 48fd0cab80e6c433455d9923d994157b SHA-1: 6b7aa395866b5f042873af719a40c4c5348957cc SHA-256: a676d135375febf317a74739598d8dbd324d91330353c80139d37d63befe9ed1
164 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code or redirecting users. Several heuristics indicate the presence of link farms and compromised CMS uploads, suggesting an attempt to host or distribute malicious files. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.
  • 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.
  • 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.phsdcenter.com/temp/js/ckfinder/userfiles/files/29889931766.pdf In PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/qd32np4hegij7vh4u90mut8p01/99956793697.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16082524236e5a---63374035158.pdfIn PDF document text
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/0hc0jfn160likji8dm9ih543s3/82110671721.pdfIn PDF document text
    • http://staropolski.net/Upload/file/refinuvanabudiraso.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/1m63vlkunsc2el0kelgbise2f7/22045736954.pdfIn PDF document text
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160717816dfe4c---69613972236.pdfIn PDF document text
    • http://www.thediethub.in/wp-content/plugins/formcraft/file-upload/server/content/files/160989a28ac4d0---fajozavivejuwenaf.pdfIn PDF document text
    • https://legouic-peinture.fr/userfiles/file/nomajugo.pdfIn PDF document text
    • http://www.northeastmarquees.com/wp-content/plugins/super-forms/uploads/php/files/22dae06e960ed2d3a1e7af11943d9f85/24999434376.pdfIn PDF document text
    • https://www.inkfactory.pk/wp-content/plugins/formcraft/file-upload/server/content/files/160757933b3357---fonaxusazosov.pdfIn PDF document text
    • https://churchofgodinjamaica.org/app/webroot/files/44482732178.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a22351c21c2---17000098561.pdfIn PDF document text
    • https://churchosonline.com/wp-content/plugins/super-forms/uploads/php/files/06713717b1fe3ebf20b60e7c1135f763/godewevexomonibozim.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c77671463df---tagimudezutosagiraj.pdfIn PDF document text
    • http://hifimarkt.eu/kunden/kronhardt/ckfinder/userfiles/files/81035436009.pdfIn PDF document text
    • http://ridendo.cz/files/file/lexupiwupokotedivemez.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=there+is+a+house+chordsPDF 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://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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e665.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE665 4944 bytes
SHA-256: d71e5c76160f72daeebbc8a42d3c5648d44c398ac272be1e34c4c4c5fe265305
font_01_sfnt_off0000f728.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF728 11160 bytes
SHA-256: 5d87f7e0562866629975a435fb5ce921ca88feb2b1e579d260920bfdf4a2e65d
font_02_sfnt_off00011cf1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CF1 16060 bytes
SHA-256: 99ddc6f5858eb134f8024171ebe717cbd02485c31471b921a5021903b5272953