Malicious PDF — malware analysis report

Static analysis result for SHA-256 d87cc96558168bcf…

MALICIOUS

PDF

76.9 KB Created: 2021-09-09 23:43:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b4e32cb17fac37f2f42ffcf5057535a4 SHA-1: f9a4d05c3379a46226030049ceac7c9abab5a0f0 SHA-256: d87cc96558168bcf7705f2df08cc1ef14606945c1d144967311a54bbd574ad48
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs and functions as a link farm, directing users to potentially compromised websites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggests these links are designed for SEO manipulation and potentially phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://synerhu.ru/uplcv?utm_term=how+to+keep+android+running+smoothly PDF link annotation
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136173b8a3f3---75723939576.pdfIn PDF document text
    • https://cgeminfos.ma/upload/file/bexokutexezevimuwuwige.pdfIn PDF document text
    • http://andlupa.com/userfiles/file/diwaxodepowosaz.pdfIn PDF document text
    • https://yifff.se/userfiles/file/vaxekofopazikufojokenerit.pdfIn PDF document text
    • http://cpbnatation.fr/fckeditor/userfiles/file/ratamupimeladebijaga.pdfIn PDF document text
    • http://kyochonbuenapark.iorderfoods.com/uploads/files/dufalokoxoxano.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1612fbf0422f23---79016298447.pdfIn PDF document text
    • https://nacituran.com/userfiles/file/jowisotojuvimam.pdfIn PDF document text
    • http://www.deep2001.com/images/library/File/53791121467.pdfIn PDF document text
    • https://partroyfuneralhome.com/partroy/assets/file/35940126989.pdfIn PDF document text
    • https://sweetburden.com/upload/users/files/pefosurujo.pdfIn PDF document text
    • https://activepymes.com/pub/file/23056158489.pdfIn PDF document text
    • https://gymlesgeants.com/upload/editor/file/40770040849.pdfIn PDF document text
    • http://linuxnewyork.com/draft/media/20185028146.pdfIn PDF document text
    • https://angkaganjil.com/contents/files/20496128917.pdfIn PDF document text
    • http://massvt.sk/editor_uploads/system/files/93334007609.pdfIn PDF document text
    • http://compsult.net/userfiles/file/menobopefefemafep.pdfIn PDF document text
    • https://sakitonus.ru/wp-content/plugins/super-forms/uploads/php/files/2ebc998619655a206eb710cd4486936e/84792277516.pdfIn PDF document text
    • http://abbwingslynnhaven.com/uploads/files/fuwazufi.pdfIn PDF document text
    • http://studiotecnicolari.it/userfiles/files/64116328341.pdfIn PDF document text
    • https://comobrew.com/newsite/images/user_uploads/file/siludi.pdfIn PDF document text
    • http://guoyangmoju.com/userfiles/files/96274614704.pdfIn PDF document text
    • https://handinhand-daycare.com/ckfinder/userfiles/files/liwipiroru.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_off0000c4f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC4F8 18124 bytes
SHA-256: 604b5a075da35b83ccbd3e25708f4452aa6eb0d5d7fb11a337beac7f9ca865d9
font_01_sfnt_off0000f45d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF45D 11220 bytes
SHA-256: be2dbd65b434ed888e64a9b6d2fd6ec3dc5f253c6935af199d53e9ea5b7e3f75
font_02_sfnt_off00010e43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E43 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1