Malicious PDF — malware analysis report

Static analysis result for SHA-256 3db353bcfa8ca048…

MALICIOUS

PDF

70.2 KB Created: 2021-06-25 13:52:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 9d150a115e5f89c2287e5ad4051bdbac SHA-1: 51d9623d2da0b2b92db5a2e76ef77e965e8736d1 SHA-256: 3db353bcfa8ca0482651dce8497e079f7fa24e7967530cb0af9d0fdac6416262
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised CMS upload directories and disposable hosting, indicating a link farm designed to redirect users to malicious sites. The ClamAV detection and ML classifier strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the PDF structure itself facilitates the attack by hosting these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://allytemp.ru/uplcv?utm_term=c%23+validate+email+address PDF link annotation
    • https://xn--1--8kcai1ck2bs.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/f8db6f1e7e9e748f468218a764cfe549/45972652319.pdfIn PDF document text
    • http://aps-mes.com/files/file/seduropep.pdfIn PDF document text
    • https://costumeworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f4a6ee665f---nokegaginodefujumoti.pdfIn PDF document text
    • http://farmina.ru/uploads/files/sujale.pdfIn PDF document text
    • http://wildpflanzen-planung.de/file/tuxelawigifetamogumaxusij.pdfIn PDF document text
    • http://kemenyseprosiklos.hu/upload/file/xegafunezizuvisojivusew.pdfIn PDF document text
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/b6u31l9ut9qp73as31len878ji/tefavar.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5fb3111818---93084530094.pdfIn PDF document text
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/1cce401cb1f09ddef9daeb7df0ba5077/terer.pdfIn PDF document text
    • https://northstarexecutivesearch.com/wp-content/plugins/super-forms/uploads/php/files/1b7292b4f267dd3d3882a48a6c9bc932/pebituxe.pdfIn PDF document text
    • https://mobistore.co.nz/wp-content/plugins/super-forms/uploads/php/files/f2d1fe050ac6def28d74778818c4c941/pomog.pdfIn PDF document text
    • https://celovechurch.org/wp-content/plugins/super-forms/uploads/php/files/1b2c0c27cd68871a096a61dc631c2800/44293785080.pdfIn PDF document text
    • https://www.allterra.group/wp-content/plugins/super-forms/uploads/php/files/eedbe12def0f68b901a235aa39062bb0/zajeboradenisumitemak.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/2d4d976406830a2658ddcaa5f88dc579/rubowadevudedolagu.pdfIn PDF document text
    • https://urbanplace.me/wp-content/plugins/super-forms/uploads/php/files/7b5fdbe6825c127f03c1b44fe1c0ac6d/rewubab.pdfIn 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://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_off0000b6e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB6E5 9104 bytes
SHA-256: fe4a9ad32d6d12da45ce8861a1e6e511df5579fd33367a5c4d1c9e774d301804
font_01_sfnt_off0000c9b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9B6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e1c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE1C8 16436 bytes
SHA-256: b24668138c6df4838ba110c4a3608676955da2fe50145a2f32b0a1d7e267e7db