Malicious PDF — malware analysis report

Static analysis result for SHA-256 b250a41228c6c4ab…

MALICIOUS

PDF

77.4 KB Created: 2021-09-02 19:50:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 9c7f84b0fb26a8e26f55ff01f22d6c7f SHA-1: 2695d1f0be8a1570dd2bfc6b9d2582d8aba9b955 SHA-256: b250a41228c6c4ab9fadcec82ddeb626bcf27f49fbadc8dfb59881c74956837f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and link farm heuristics, indicating it is designed to redirect users to other malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. While no scripts were directly extracted, the structure and URL patterns are consistent with a malicious PDF dropper.

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://laborke.ru/uplcv?utm_term=codigo+penal+federal+2018+pdf+camara+de+diputados PDF link annotation
    • http://mrcookie.tw/upload/editor/file/030256343525.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/160aea2194624f---rifuretamurigin.pdfIn PDF document text
    • https://balaji-technology.com/userfiles/file/nuxovagefaje.pdfIn PDF document text
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/b8e83n99n868bl82hhea7hrrdf/sovavigakepotox.pdfIn PDF document text
    • http://muacuoi.vn/Pictures/files/56019314451.pdfIn PDF document text
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/e92ab3ae6427d4c3c7b377d889423973/kesuko.pdfIn PDF document text
    • http://rcp-ranstadt.us/files/1014817835.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f7f8df252e2---90371084120.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/llmj72dt0h6ooabkb2h46u1vh6/gotexupuwerazolujesapisej.pdfIn PDF document text
    • https://bibliothequeanglaise.org/upload/files/79169643746.pdfIn PDF document text
    • https://toppelletmachine.com/d/files/72534200838.pdfIn PDF document text
    • http://happysmilecard.com/uploads/files/25436148628.pdfIn PDF document text
    • https://agmatbaa.com/upload/files/gotokufilurizaruriripi.pdfIn PDF document text
    • http://uptownherndon.com/uploads/files/31899620714.pdfIn PDF document text
    • http://haumeaonline.com/userfiles/file/9342608072.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160876e5b44474---87097471024.pdfIn PDF document text
    • http://www.ddd-iasi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1606ee58a922c5---9625025299.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e3e5f73d01---sanidogawepukojif.pdfIn PDF document text
    • http://sendedianqi.com/upload_fck/file/2021-6-25/20210625210216310319.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1bdbbc3a36---lugidezakutun.pdfIn PDF document text
    • https://jnfarley.com/wp-content/plugins/super-forms/uploads/php/files/g21emg2n849ldq7stluiv8ek66/lariwepegafomira.pdfIn PDF document text
    • http://proxima-design.cz/files/file/nukikenolemilelalelot.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_off0000c5f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5F3 18160 bytes
SHA-256: 72158727e4a6417283e8966ec2de36c97e82d6f795ea86a6ff8507ce54d89ed8
font_01_sfnt_off0000f417.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF417 11596 bytes
SHA-256: 496dc599a3b860214f1b927785be6f7917b1a0e9dcf272faa20902e7cdcbaeab
font_02_sfnt_off00010f94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F94 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1