Malicious PDF — malware analysis report

Static analysis result for SHA-256 258a4cf5ca1d9a72…

MALICIOUS

PDF

78.3 KB Created: 2021-06-26 20:15:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 729e3772eb95baa90dbcf82382894867 SHA-1: 438625401cc5282eaa79d7d5738cd80286a4ba79 SHA-256: 258a4cf5ca1d9a72c11e7cac929b6da18bc06ef07ce819035c3b9db4074835b1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised WordPress upload directories, suggesting a link farm designed to redirect users to malicious content. The presence of these links and the overall structure align with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://kakvkusno26.ru/wp-content/plugins/super-forms/uploads/php/files/1b2c69e0fb3fe3af2477f4befb91e8df/33347142528.pdf
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/bv000vt9cj1tg72qdmqa4akb96/11584474455.pdf
    • https://bamor.org/userfiles/file/juwop.pdf
    • http://crystalsteakandstogie.com/clients/1/1d/1dbb6d5698303b6304ae84622e226a19/File/ledutakowezofopufax.pdf
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/820cc3fc1f24602d1e4fef9a7c7ff58e/55901312448.pdf
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a43ada1b87f---44422620848.pdf
    • http://ecbpolska.pl/wp-content/plugins/super-forms/uploads/php/files/21e7350158d94f45196a2cdbeb53f59c/sufumiwatu.pdf
    • http://limoride.net/gallery/file/35506175654.pdf
    • http://xpressup.com/userfiles/file/12868894968.pdf
    • http://robwalker.net/fckupload/file/97101733579.pdf
    • http://yngc.ru/admin/ckfinder/userfiles/files/57307953471.pdf
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/092d1s7bk4t6g60rugqq0emou3/29726372814.pdf
    • http://lilit-realty.com/wp-content/plugins/super-forms/uploads/php/files/ni2nmndm84h0tlj706tj7ue8q1/pagabe.pdf
    • http://teusz.pl/UserFiles/file/87232844713.pdf
    • http://www.zulfugar.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b32fe7b3eda---73168236012.pdf
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160831c1ee58ae---94168171486.pdf
    • https://pankalconstructora.com/wp-content/plugins/formcraft/file-upload/server/content/files/160772360a789b---zalakofuxopovemovemaxutad.pdf
    • https://proff-doors.ru/wp-content/plugins/super-forms/uploads/php/files/111e9ed0e79477ae74fe9e463aa273d4/vomapanisozewarasagumipo.pdf
    • http://happinessgown.com/upload/users/files/kuxinipesakakerakasasiw.pdf
    • http://guides2alpes.fr/uploads/file/98468288040.pdf
    • https://www.endthestigmacounselling.com/wp-content/plugins/super-forms/uploads/php/files/nveq7d3h4056qf5c9u8e000bok/4869371427.pdf
    • https://beautyyaurient.com/editor_upload/file/xewosuxoruxodifaramibare.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160bf8389a8765---gorepusuwuzorotifitu.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=high+paying+jobs+for+students
    • 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_off0000cfb8.bin
be44a3a54b7483825f3f08a2a68dad9e03ff98af8f0ed88dbaf419ff238348d9
pdf-font-stream PDF embedded font (sfnt) at offset 0xCFB8 11208 bytes
font_01_sfnt_off0000e96f.bin
f6cc6116f6a7852518fa2146cf379e6f054d74564a82050be422d8fefb9f2b45
pdf-font-stream PDF embedded font (sfnt) at offset 0xE96F 16352 bytes
font_02_sfnt_off000113d7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x113D7 16792 bytes