Malicious PDF — malware analysis report

Static analysis result for SHA-256 a11529b1e4a66068…

MALICIOUS

PDF

87.8 KB Created: 2021-07-08 19:17:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: cfebbfda520982a1ead48463c126d317 SHA-1: 230147a8dd2b09dcb45ea7f390c0ee4bd05890d3 SHA-256: a11529b1e4a660689632e965debd6174c0040a2a714550679b538d09e22b73f5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains a link farm pointing to multiple compromised WordPress sites, suggesting a phishing or malware distribution scheme. While no scripts were directly extracted, the presence of numerous external links on compromised infrastructure strongly suggests the document is designed to lure users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9946

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://www.energetisch-therapeut-estie.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16080b10f2ae24---29911685538.pdf In PDF document text
    • https://praward.tw/wp-content/plugins/super-forms/uploads/php/files/ab930ae40dba838c0f42c7a4a80c08fb/wetifufidon.pdfIn PDF document text
    • https://realestateconnect.pro/wp-content/plugins/super-forms/uploads/php/files/qb01a62jicq9fum9pr8ipkcg01/42623737596.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/829b760e4ef7b4bf9f05654309ad5047/72799001846.pdfIn PDF document text
    • https://smilepath.com.au/wp-content/plugins/super-forms/uploads/php/files/0509c67ec8898784366217b82b64990d/62288647924.pdfIn PDF document text
    • https://coil.hk/upload/files/lozidosilejal.pdfIn PDF document text
    • http://shengnabei.com/uploadfile/file///2021061622453620.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1606ff7c41510b---28292370497.pdfIn PDF document text
    • http://provia-events.de/pics/fotos/1/file/rarumipo.pdfIn PDF document text
    • http://begemot-rus.com/uploadfiles/file/2021062009242273499.pdfIn PDF document text
    • http://serdceprirody.ru/userfiles/file/99543359300.pdfIn PDF document text
    • http://lushexperiences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607effe6c121d---kamafeneramu.pdfIn PDF document text
    • http://safeabortionnepal.com/userfiles/file/28619568685.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/160816a7809719---92011328772.pdfIn PDF document text
    • http://www.grundys.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160dd642dea4b5---50212954585.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160ab4c1f23acf---98048138869.pdfIn PDF document text
    • http://salocchi.it/userfiles/files/63190205080.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/a3634c0b8b5312f624ee97c20ac2209e/timab.pdfIn PDF document text
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/160da3c68e38d6---45180566630.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/097414f6a427e85e6e576ec91ed27fad/vusolirasitolaxetono.pdfIn PDF document text
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/540a3e6c82645e77cafc071552be5c34/50333974112.pdfIn PDF document text
    • https://carpanea.it/wp-content/plugins/super-forms/uploads/php/files/823de7d65c12d0b0dbb41a14ce336dd8/74677429741.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=acids+bases+and+salts+class+10+notes+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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000df53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF53 16140 bytes
SHA-256: 00b1f632e8afe72716c8bcdb76b7901b56c060d1dc0f96f3f5c1b8373b85735b
font_01_sfnt_off0000f4cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4CF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010ce6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CE6 10808 bytes
SHA-256: b21a90c7deb237d77ed7285a9b2430818fa22f05a95686bb3bf2ac4fbc82fd26
font_03_sfnt_off000125c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125C2 16788 bytes
SHA-256: 1f4c4329d8d84da105ecb314e8de85b8e31cfe53a4f00d599510fffc4f42bb1f