Malicious PDF — malware analysis report

Static analysis result for SHA-256 8528133634ba981b…

MALICIOUS

PDF

72.2 KB Created: 2021-09-12 04:38:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9e35dfe05d56e84272245e6dcee10e77 SHA-1: e8807898410ba0238888ba2351bd1b954782d78e SHA-256: 8528133634ba981bdc704ee137acd57ce967d38eb6fb8188fd7b2966e65c6b7f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is a PDF file identified as malicious by ML classifiers and ClamAV. It contains numerous links, many pointing to compromised CMS upload storage and disposable hosting, suggesting a link farm or SEO spamming attack. The embedded URLs and the nature of the heuristics indicate an attempt to redirect users to potentially harmful content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://imagebeaute.fr/userfiles/file/rumevupo.pdf
    • http://pnktools-th.org/ckfinder/userfiles/files/didilax.pdf
    • https://spotiverify.com/ci/userfiles/files/4423612227.pdf
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/dd25206c9858778ea5382445e51e1538/11713942231.pdf
    • https://www.horisunmauritius.com/wp-content/plugins/super-forms/uploads/php/files/7ec60c87537bb45f3bcb5290d7cad36a/38475063420.pdf
    • https://luckyfood.itweald.com/uploads/files/613bf5bddca36.pdf
    • https://kclandscapes.com/ckfinder/triplebuserfiles/file/75201250013.pdf
    • https://gresathouse.com/wp-content/plugins/super-forms/uploads/php/files/0bb227637ce6511f75c123e11c40108c/tedamirepomusapes.pdf
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613b263870ec9---59389157306.pdf
    • http://easternhoteljeju.com/FileData/ckfinder/files/20210907_D44B97B64CE1CCED.pdf
    • https://morganmethod.com/ci/userfiles/files/pubapamix.pdf
    • http://phanmemerp.vn/attachment/files/92843477795.pdf
    • http://federicozucchettiarchitetto.eu/userfiles/files/40778725691.pdf
    • http://africareview.in/userfiles/file/83521257156.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613247a843588---16647836573.pdf
    • http://elitsatodorova.com/uploadfiles/file/mijabowanigidu.pdf
    • http://msslink.ru/userfiles/files/38947415939.pdf
    • http://kriosispl.com/cote_dor_import/admin/ckfinder/userfiles/files/sobivorogofefibewujutabej.pdf
    • http://himalayakebab.com/shipinc/userfiles/files/46953114080.pdf
    • http://cheliabinsk.realxenon.ru/uploads/files/midudir.pdf
    • http://meyergarden.com/ckfinder/userfiles/files/fozeg.pdf
    • http://hiroshima-teishaku.com/userfiles/file/daguvigurebuzijudoma.pdf
    • http://cherryontop.pl/upload/fotki/file/59215704435.pdf
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138f2fd76969---fusogifijomufoj.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=hanuman+chalisa+pdf+in+odia
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b680.bin
92d7151d9c2002edf5b528e63f4daeaf8dffaab118ffefec8d5420513803a46f
pdf-font-stream PDF embedded font (sfnt) at offset 0xB680 17152 bytes
font_01_sfnt_off0000e341.bin
699923451c4a39698d5d232cde072d70eda99a8b4db869059c1d432c96fc5328
pdf-font-stream PDF embedded font (sfnt) at offset 0xE341 10648 bytes
font_02_sfnt_off0000fb50.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFB50 16792 bytes