Malicious PDF — malware analysis report

Static analysis result for SHA-256 25581729a5416aeb…

MALICIOUS

PDF

86.6 KB Created: 2021-10-07 01:13:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 182ede0969c529aa5d3aeb1b6e36fc52 SHA-1: ec29fee785667795e8f905100a257a28ddcda525 SHA-256: 25581729a5416aeb354aaead66ca13ec50ccd4faf1b21729f7e9c67c45a05ff4
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of embedded JavaScript, although not fully analyzed due to obfuscation, further supports the attack pattern of luring users to external, potentially malicious, sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://saigonservices.vn/images/uploads/files/zasunelenaxeliviwawanevud.pdf In PDF document text
    • https://turkihale.com/userfiles/file/In PDF document text
    • http://tomasmrazek.cz/userfiles/file/dikosefatixonuv.pdfIn PDF document text
    • https://guruamardaspublicschool.com/userfiles/files/ravibumapefu.pdfIn PDF document text
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/atbsdnlpagrqeo5sc1pm8l8v72/daxazunofa.pdfIn PDF document text
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/75d288658ef8868318b52260884a5f11/rojoketuri.pdfIn PDF document text
    • http://rw-hse-businessconsulting.de/userfiles/file/nigenivixilen.pdfIn PDF document text
    • http://palakkadtourism.in/ckfinder/userfiles/files/26539514296.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16142422c7b112---46864430150.pdfIn PDF document text
    • http://pyramidplaster.com/file_media/file_image/file/60347871145.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/16141d372ed384---taxipebixelaxugetesik.pdfIn PDF document text
    • http://petra-dario.info/upload/datoteke/soriz.pdfIn PDF document text
    • https://franchise-vietnam.com/app/webroot/img/files/pevelifuwem.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144aa9b7c298---28532259481.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/9dd578981b109cc4ace40309d25d88a3/voxexowubiteriledabinew.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dceda8ad1d---15513395974.pdfIn PDF document text
    • http://bobas24.pl/Upload/file/filodadewinenuvexu.pdfIn PDF document text
    • http://envigest.cz/upload/file/87344162581.pdfIn PDF document text
    • https://sonntag-immobilien.lu/userfiles/files/7850507096.pdfIn PDF document text
    • http://bjerkelunden.org/content/files/userfiles/file///6717490112.pdfIn PDF document text
    • http://izeninfo.net/admin/upload/files/24142986219.pdfIn PDF document text
    • http://jingmingtai.com/filespath/files/20210924234328.pdfIn PDF document text
    • http://pizzeria-millemiglia.de/app/webroot/img/editor/file/85462084384.pdfIn PDF document text
    • http://kanoonkaraj.ir/dbmanager/filebank/htmlgallery/file///175004710.pdfIn PDF document text
    • http://kstarsmall.net/userfiles/file///dujufomokef.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=creation+answers+book+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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e6af.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6AF 10792 bytes
SHA-256: cfda5e93b30f9e8d4221d3f60f88cbe32427bc1d5668b4ca7c8df363eb077a27
font_01_sfnt_off0000ff8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF8A 19932 bytes
SHA-256: d4c2d64544aa31a70495d285128401d891f864097288b24073203cf321ec3849
font_02_sfnt_off0001341a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1341A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1