Malicious PDF — malware analysis report

Static analysis result for SHA-256 151edf0adc16a863…

MALICIOUS

PDF

69.5 KB Created: 2021-10-02 15:16:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 56e863bc97520aa71ea9224ee9afa47c SHA-1: c9bd9f1e9c642e138cb8b9a746bf6d926418c6c1 SHA-256: 151edf0adc16a863f49728b0571bdcf8dfb27d6ca66977c3b19827aa8df717c4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and also by an ML classifier. It contains embedded JavaScript, which is often used to exploit PDF vulnerabilities or redirect users. The document also features a link farm pointing to compromised WordPress upload storage, suggesting an attempt to host malicious files or redirect to phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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 http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161372640d13a3---47464475309.pdf
    • http://emke.hu/uploads/ckfinder/userfiles/files/44428112147.pdf
    • https://www.simcoerecovery.net/wp-content/plugins/super-forms/uploads/php/files/tfl0fgeoseugt6f5vjd8gvot26/88158628757.pdf
    • http://findusafranchise.com/files/files/jodejiviwurere.pdf
    • http://dreamsurgeryen.net/ckupload/files/bomufoputoba.pdf
    • http://craftland.de/res/wysiwyg/file/76189309097.pdf
    • http://mu-rrrc.com/userfiles/file/sigipezatotekipimixax.pdf
    • https://kolbandibileklik.com/resimler/files/32813245302.pdf
    • https://vroa.pl/chplusfiles/file/lezem.pdf
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1613dfe8bc09c8---tuviwuduguvog.pdf
    • http://ourconn.com/userfiles/file/202109082204359359.pdf
    • http://bajkolandia-leszno.pl/userfiles/file/wupagadofamatajaruno.pdf
    • http://anhuizpyy.com/upload_fck/file/2021-9-20/20210920015142256608.pdf
    • http://southerncross-ex.com/images/blog/file/pisivenexikosojodufegose.pdf
    • https://www.vek-bg.com/app/templates/js/ckfinder/userfiles/files/98005255017.pdf
    • https://gtijsr.com/userfiles/file/43455594407.pdf
    • http://lokalsport.no/userfiles/file/56799703064.pdf
    • http://suvagcentr.ru/userfiles/files/74689464504.pdf
    • http://aven.su/userfiles/file/25191083338.pdf
    • https://izharfoster.com/wp-content/plugins/formcraft/file-upload/server/content/files/16142d0180a57a---sedixutalizufodudigef.pdf
    • http://casaperugia.fr/userfiles/file/piruveguzuk.pdf
    • http://ajk-opakowania.eu/upload/fck/file/77113457759.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=small+heart+aches
    • 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_off0000aeeb.bin
3163656f83402b3ceb56437947d0379fd30d5b861989becdfff351b4113b7739
pdf-font-stream PDF embedded font (sfnt) at offset 0xAEEB 16744 bytes
font_01_sfnt_off0000d99b.bin
bb4949aab700ed48fdf815d9f3af3858aa46bee58ab0e5b86b11ef985fa5e461
pdf-font-stream PDF embedded font (sfnt) at offset 0xD99B 10256 bytes
font_02_sfnt_off0000f0a3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF0A3 16792 bytes