Malicious PDF — malware analysis report

Static analysis result for SHA-256 508f9b26ac87e6dd…

MALICIOUS

PDF

69.6 KB Created: 2021-09-26 19:48:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: c44794d445453124129e66ff57912d1a SHA-1: a351e5d6e7bdbd42ce38ed927c499dacae7c84dc SHA-256: 508f9b26ac87e6dd0932060798f32411e6785d448955ad1fb1de65781899dc1b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, directing users to various URLs, some hosted on compromised WordPress sites, under the guise of software downloads. The presence of external URIs and link farm heuristics strongly suggests an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://philabc.ru/uplcv?utm_term=download+infinite+flight+simulator+latest+version PDF link annotation
    • https://burgaseguros.com/userfiles/file/nozodidateganudunofa.pdfIn PDF document text
    • http://www.asap-recruitment.net/upload/file/60998596718.pdfIn PDF document text
    • http://projecthouse.bg/uploads/CKfinder/files/xexifawajizolinikutuvinuf.pdfIn PDF document text
    • https://onlinendttraining.com/files/54633102510.pdfIn PDF document text
    • https://travelinnsuites.com/nbloom/fckuploads/file/27909949250.pdfIn PDF document text
    • http://handsonmontessoripk.com/userfiles/files/nizagefekesuno.pdfIn PDF document text
    • https://thaiwoodengames.com/files/upload/files/sokogivomutuvomaxomewo.pdfIn PDF document text
    • http://mnarch.it/userfiles/files/fagirotawokela.pdfIn PDF document text
    • http://agriturismolionsfarm.it/userfiles/files/ropebekalatupev.pdfIn PDF document text
    • http://kledingindex.nl/images/uploads/zasemajezezogufotemikofex.pdfIn PDF document text
    • http://suarezbeltran.com/aym_images/files/20164710679.pdfIn PDF document text
    • https://drrajanmahtani.com/userfiles/files/61189103761.pdfIn PDF document text
    • https://rpdev.org/ckfinder/userfiles/files/91451561942.pdfIn PDF document text
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/16148522f18836---41425209746.pdfIn PDF document text
    • http://gocreate.termall.pl/upload/fck/file/dumajoponejedaxe.pdfIn PDF document text
    • https://needletherapy.eu/upload/file/31644071842.pdfIn PDF document text
    • http://onlinecommerce.bg/uploads/pages/files/16315272611.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614ef044045f9---baluruvujibukizoxofef.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1614e17161152e---wajejirelutunelewesawusek.pdfIn PDF document text
    • http://gsnursing.in/ckeditor/ckfinder/userfiles/files/87579588288.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_off0000af4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF4E 15620 bytes
SHA-256: e3eb1ef79feb12ad55db3c0f63b12ebaf378476b1c896910d8da760810828abd
font_01_sfnt_off0000d73e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD73E 11056 bytes
SHA-256: f920b64478e71af7389b3a79dabcab1f44c996aab2514bbf53ac5577a97c6af9
font_02_sfnt_off0000f09a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF09A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1