Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4b23b5542240c36…

MALICIOUS

PDF

133.7 KB Created: 2021-06-20 01:41:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-18
MD5: 846a3f9d6ff9a61f4728f6815fbb9572 SHA-1: e0baae125cb9c2ec08328ded4299e6c47087ed9f SHA-256: f4b23b5542240c36285497105b117ba6f6207946ddc892a063a8bce5010b2c0f
156 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • 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.
  • 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://infrive.ru/uplcv?utm_term=minecraft+java+download+apk PDF link annotation
    • https://sckstone.com/wp-content/plugins/super-forms/uploads/php/files/49a2ba864beb8f10afe7771b8057f1ed/52407852509.pdfIn PDF document text
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/241f34245bbd05a7b0c0ada12658a7d2/76998887909.pdfIn PDF document text
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/b665ad0b3da8fb7e0cefd98101aad5c7/3829729692.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/1607e20d97733b---51382908024.pdfIn PDF document text
    • http://aj-logistics.com/stock/userfiles/file/87143477689.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b28c173a8e6---17244688511.pdfIn PDF document text
    • https://auto-rujo.com/images-editor/file/roxekipawegunozuxobif.pdfIn PDF document text
    • http://bugaboo-buffalo.eu/UserFiles/File/39152453665.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160a984a325ddb---ledosomaketuxozopizij.pdfIn PDF document text
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/820943d6720325448e9a7027a76b8079/14055824267.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078aa5e596fc---vapejatazizegunilefazuval.pdfIn PDF document text
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cd1cc992871---75345426779.pdfIn PDF document text
    • https://xn--80aaaglcftt5alesfkk7f.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/438e7aeb4b8b044ce5f62ae5fad03b5e/xetobisuguwure.pdfIn PDF document text
    • http://copelandreunionla.com/clients/6/66/66f6f3de7053633686652f51c4c00696/File/jevofilutokozek.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c29345ae6a1---laravaxuviruregosusikibim.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001a7ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A7AE 5056 bytes
SHA-256: 12acbe4d96ba62d55e03b16c08c67b3e8b54512486214a0d57482e6c1686c1e7
font_01_sfnt_off0001b8f6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B8F6 2676 bytes
SHA-256: 056e9e5597f70ae6600766ecacea3915cdac9abb0a1e41cc0134f6700d6eddd7
font_02_sfnt_off0001c41c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1C41C 11736 bytes
SHA-256: ce16afa28ced998350baf2d775c6bc243a2ff5f94f83fbc03178c71f5fb32aef
font_03_sfnt_off0001ec56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1EC56 16212 bytes
SHA-256: 6feead338415d61a86e883b689f9875f16a3c5ff9126e5f738a4e17f766aaf5d
font_04_sfnt_off0002019e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2019E 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2