Malicious PDF — malware analysis report

Static analysis result for SHA-256 b27a77e5765d5c50…

MALICIOUS

PDF

93.4 KB Created: 2021-07-20 00:29:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 3d5fc92e0a4d25df3c2f8a575ded35c1 SHA-1: 9d5750d8ee14ab039ba9771c4d800807e57fb076 SHA-256: b27a77e5765d5c50bcb4b5db9b26302e72a354f19ec43478c03d85e3d132d93f
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites, likely serving as a distribution point for further malicious content. The presence of multiple distinct hosts and the use of 'utm_term' parameters suggest an attempt to leverage SEO or phishing tactics to lure victims.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16078ee730c611---kopijaxilagolerebeguro.pdf In PDF document text
    • http://walthamclassof1985.com/clients/5/52/52060312c10aa816a718e90a19a6a7a1/File/vetewujofodo.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/775973d67ae3274c76a700035a887b0a/87255000409.pdfIn PDF document text
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/160de1c0078acc---78891745163.pdfIn PDF document text
    • https://pfgmm.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a04f61ec9e0---33002246216.pdfIn PDF document text
    • https://catwalkdogcome.com/editor_upload_image/file/gimaxaruzumafuzipeletife.pdfIn PDF document text
    • https://www.ptlittleflower.org/wp-content/plugins/super-forms/uploads/php/files/1t75bn9fiq5ehoaoefaj8cajik/josimovevajefalasep.pdfIn PDF document text
    • https://www.geosuiteonline.de/wp-content/plugins/formcraft/file-upload/server/content/files/160d9bfd62ab4a---pozumasapezajanedur.pdfIn PDF document text
    • http://sentezetutmerkezi.com/upload/ckfinder/files/zukejuzotuxexadeladomaz.pdfIn PDF document text
    • https://www.citysecurity.org.uk/wp-content/plugins/super-forms/uploads/php/files/bcetggj1rl818juepi5h8sr272/puninixelipusekalalufokur.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160ee8870b2704---91222627696.pdfIn PDF document text
    • http://balcimimarlik.com/resimler/files/tedalavipog.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a35214e4e62---vidudubilazebabuwuve.pdfIn PDF document text
    • https://fedico.ca/upload/editor/file/gasasawenadosajud.pdfIn PDF document text
    • http://www.191seo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ca9fdbf3c5---41863062191.pdfIn PDF document text
    • http://tai-group.com/upload/files/86291834370.pdfIn PDF document text
    • http://vincitydata.com/uploads/ckfinder/files/gakafuripesag.pdfIn PDF document text
    • http://mikailang.net/userfiles/file/20210507042615_142619180.pdfIn PDF document text
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/68b997ad9dd6555b59b182550e28ddfb/43601854502.pdfIn PDF document text
    • https://hizlipin.com/calisma2/files/uploads/lutitowunadimitiwozunuw.pdfIn PDF document text
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/42d45e6c9eafaf5246ca33539032ee96/80913246484.pdfIn PDF document text
    • http://zuche0551.com/upload/file/fakugowe.pdfIn PDF document text
    • https://thewaves.net/wp-content/plugins/super-forms/uploads/php/files/tt9bgkarbak8bd78phqck67gjt/26418817888.pdfIn PDF document text
    • https://digireg.com/upload/49473947261.pdfIn PDF document text
    • https://cashmeredreams.com/wp-content/plugins/super-forms/uploads/php/files/a6c5918e8fa79f1cfafdb550312b28fa/23971679113.pdfIn PDF document text
    • https://jaiminsales.com/ckfinder/userfiles/files/84262827774.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=king+of+the+roll+board+gamePDF 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_off000109ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109BA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000121cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121CC 17728 bytes
SHA-256: ca5fc12b67515519bc67e3c09029b98d456041c528e73df27f90a254e99639dc
font_02_sfnt_off0001501c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1501C 10764 bytes
SHA-256: 7cf1af6f9fea4089a9ed0d0171e192a5c6e9955bff3cfd1ac0a420c3c6041f81