Malicious PDF — malware analysis report

Static analysis result for SHA-256 f7f3eb576d31ce90…

MALICIOUS

PDF

86.9 KB Created: 2021-09-07 22:38:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 149420e0358748fa748b48ab89b79b24 SHA-1: 1ee016bf17d68dc7c2918f15c5d79a244850376e SHA-256: f7f3eb576d31ce9023de98b8208e9b238981788842274ca2ec378d5510a30913
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS uploads or disposable domains. The embedded URLs suggest an attempt to redirect users to malicious content or further stages of an attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://postele-z-masivu.sk/ckfinder/userfiles/files/72534914904.pdf In PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/16078d2723fe5a---43457558946.pdfIn PDF document text
    • http://grandinhr.eu/images/user/file/1059006822.pdfIn PDF document text
    • https://raiporjai.com/piceditor/file/zelijogejomawef.pdfIn PDF document text
    • https://ddshower.com/ckfinder/userfiles/files/bukoxopusavigogu.pdfIn PDF document text
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8d35c8cc64---41106233968.pdfIn PDF document text
    • https://maftplayer.net/calisma2/files/uploads/3743223685.pdfIn PDF document text
    • http://kingtonkatsu.com/uploads/files/dopuritenujopimox.pdfIn PDF document text
    • http://ecilingirler.com/resimler/files/31713928861.pdfIn PDF document text
    • http://hitecds.com/userfiles/file/migowufemijoxofa.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608d00bc40450---29040691017.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/50cb41a72c194143b1a010d7bb5f8576/wopibuwozigegomago.pdfIn PDF document text
    • http://clubesquilacoma.com/uploads/files/lulanowopozatarujik.pdfIn PDF document text
    • https://portalbime.com/UploadedFiles/New/file/zojaniwakake.pdfIn PDF document text
    • http://xn--b1agjlwjc3g.xn--p1ai/ckfinder/userfiles/files/54712647134.pdfIn PDF document text
    • http://www.77ice.com/upload/files/78105229161.pdfIn PDF document text
    • http://saddabro.com/userfiles/file/48225449887.pdfIn PDF document text
    • http://kimhoatra.com/upload/fckimagesfile/rufizek.pdfIn PDF document text
    • https://amgaa.org/temp//files/bipugonakiremarulemonur.pdfIn PDF document text
    • http://thsport.dk/userfiles/file/49872915848.pdfIn PDF document text
    • https://maria-galland.ru/files/file/sokanogubik.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1607bc050eeea1---nesudalazivetewoja.pdfIn PDF document text
    • http://ejmk.com/ej/upload/files/dutosopibu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=sophie+fontanel+une+apparition+pdfPDF link annotation
    • 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_off0000e76b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE76B 21336 bytes
SHA-256: e7ff9afc4530c622143e8030db38515b6046d71a1dacee6a1613f05ba49778a6
font_01_sfnt_off00011d4f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D4F 10604 bytes
SHA-256: c071ef22cf07fe58b65aad7a8668ba92e8fea8c5d833658298b3666f31c1e553
font_02_sfnt_off00013576.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13576 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1