Malicious PDF — malware analysis report

Static analysis result for SHA-256 a723ebca5e8f986f…

MALICIOUS

PDF

81.8 KB Created: 2021-07-09 19:55:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 105af391affc090f5ec034ad0eaf63a0 SHA-1: 34a476b3630e9de0e636a5d262dc7fc560351020 SHA-256: a723ebca5e8f986f494c72a8669210ffe8b590bafe8fb7b0fce9b10a7da09022
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file that exhibits characteristics of a phishing lure, as indicated by multiple heuristics related to link farms and compromised CMS uploads. The embedded URLs point to various domains, suggesting an attempt to redirect users to malicious content. The ML classifier and ClamAV detection strongly support its malicious nature, likely serving as a phishing document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://coretry.ru/uplcv?utm_term=principles+of+management+pdf+notes PDF link annotation
    • https://apizf.org/public/file/8032078754.pdfIn PDF document text
    • http://saludocupacionalpso.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/16078129516240---14552416168.pdfIn PDF document text
    • http://guchenes.com/d/files/fusuzuli.pdfIn PDF document text
    • https://www.ideaklinik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160c9eefc7a3c5---gedapidinafikagonagoni.pdfIn PDF document text
    • http://ebiocell.com/uploadfile/file///2021060108030768.pdfIn PDF document text
    • https://hoffmanowska.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160d20f457f8ab---76422243208.pdfIn PDF document text
    • http://hesexpo.com/img/editor/image/file/70202554619.pdfIn PDF document text
    • http://staging.impactredevelopment.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082040f0f8ad---bujitegapazu.pdfIn PDF document text
    • https://poolpoint.be/uploads/file/kosukukiduf.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160807cd9afbd1---43608210277.pdfIn PDF document text
    • https://www.hospedeagora.com.br/wp-content/plugins/super-forms/uploads/php/files/gqtnqk6sfin09feli166df3f5l/12850423466.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/f0786d1e76fa1ce4af3835505057d23a/84514270430.pdfIn PDF document text
    • https://windsbs.biz/files/file/vikosadorerixidowapufat.pdfIn PDF document text
    • https://certifiedmoversinc.com/wp-content/plugins/super-forms/uploads/php/files/cd3021cf9052cf26eebd97a9acd4f390/fakufov.pdfIn PDF document text
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/87db1a849abdd08c8a1fef133daadade/tusegarofenowuj.pdfIn PDF document text
    • https://medicentrumnz.eu/medicentrum/files/file/jafab.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160735b180e40b---8365252118.pdfIn PDF document text
    • http://otoozevran.com/resimler/files/vekikogadojofozobamat.pdfIn PDF document text
    • http://altaprecision.com/userfiles/file/6278882417.pdfIn PDF document text
    • https://hometeamcorp.com/images/usr/wuvusi.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://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_off0000dfd5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFD5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f7ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7EC 10964 bytes
SHA-256: c93c032c2f313cc7e4b5063376ddeb4fe4ad3f7e3e242402590c40798a334ad6
font_02_sfnt_off0001111b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1111B 17448 bytes
SHA-256: 4ddc1e18db3b9cb16d9a5ad10c9ace516e9295382014d77b8bd2ff1cf5742248