Malicious PDF — malware analysis report

Static analysis result for SHA-256 280937aa42b3d1a8…

MALICIOUS

PDF

81.0 KB Created: 2021-09-07 12:56:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: e5f1a9b99fddefbac1f0e4c04e283e99 SHA-1: 9e736b785fff32922a5f43a9bef6b1bcae1d29fe SHA-256: 280937aa42b3d1a80410a7be02f3eab61d5ac0bac0729743ffe6e2d685966ea5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The document contains numerous external URIs and link farms pointing to compromised websites, suggesting it is designed to redirect users to malicious content. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this, indicating a tactic to leverage compromised infrastructure for distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://catamma.ru/uplcv?utm_term=efficient+market+hypothesis+pdf+notes PDF link annotation
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16089b49c7e0ee---39572707585.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/16aj8cgejp5b9unuqbrru47r0p/76338874159.pdfIn PDF document text
    • http://bajajsports.com/userfiles/file/7736510230.pdfIn PDF document text
    • https://ewastexperts.com/userfiles/files/fedevaturupodeduga.pdfIn PDF document text
    • http://teresachild.com/upload/files/71199791326.pdfIn PDF document text
    • http://asupuro.com/upload/save_image/files/wudesilelu.pdfIn PDF document text
    • http://capitaldanceacademy.com/userfiles/files/furenane.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/mr4q471oivrfmshavn9btvodck/wisokeduguxewesazerotoje.pdfIn PDF document text
    • http://aihyang.com/userfiles/file/76657515923.pdfIn PDF document text
    • http://nguyenquangcomputer.com/upload/ck/files/zoxugusegikofivibomasamu.pdfIn PDF document text
    • http://melissajacksonmd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160728d7575a52---52165075593.pdfIn PDF document text
    • http://alkanboya.com/files/file///zudatobusig.pdfIn PDF document text
    • http://hum-lucknow.org/test/fckeditor/file/17425291815.pdfIn PDF document text
    • http://aivieksteslaivas.lv/userfiles/file/sesomi.pdfIn PDF document text
    • https://himanshikitchen.info/viking1/uploads/files/72547221066.pdfIn PDF document text
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1609072238e350---dafomavaxelerut.pdfIn PDF document text
    • http://naturallabs.de/userfiles/file/2856129835.pdfIn PDF document text
    • https://notofthisgalaxy.com/wp-content/plugins/super-forms/uploads/php/files/8c3m0dqug5goas8kn9u7256pab/levajiwivovirimizumesobeb.pdfIn PDF document text
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/2fcab39a7c52733581f6f2ebb8f5c2b0/23194676718.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/0a5031d22a7c74c53736803b72da79f3/29827762549.pdfIn PDF document text
    • http://soosanfix.com/upload/fckeditor/file/85678923118.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/ub0g3fd3lqabokus0urbg04sp1/wamawikosezimut.pdfIn PDF document text
    • https://laplacedesstores.com/upload/file/50048310446.pdfIn PDF document text
    • http://livingkaneohe.com/userimages/xixinunusobudotepul.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_off0000da44.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA44 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f256.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF256 16660 bytes
SHA-256: b54270dd3106b1f9ad6c401ef9e0c983838880975cdfa36c1391ac66b87d5396
font_02_sfnt_off00011cc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CC8 11028 bytes
SHA-256: 1ebadbae1ef282aa1eb832d588e9a37913c71258a22edc19a20222351a967bf1

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