Malicious PDF — malware analysis report

Static analysis result for SHA-256 a135519611312dae…

MALICIOUS

PDF

94.8 KB Created: 2021-09-02 18:16:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: fd64c9b1e2eda564de397f5bb1211555 SHA-1: 4fa76a0e95399886a144e9b378edc6c25b05b5f5 SHA-256: a135519611312dae1205bb8c38c2c77a8c525fab333771115b33da93deb8b8dc
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, which is a common technique for executing malicious code within PDFs. It also features numerous external URIs, many pointing to compromised WordPress sites, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

Heuristics 7

  • 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.
  • 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 https://allytemp.ru/uplcv?utm_term=crioterapia+en+deportistas+pdf PDF link annotation
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611ad89c92f43---laxizituwu.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e04aee60b4---53496413506.pdfIn PDF document text
    • https://alcoolassistance-creuse.net/www/site/js/ckfinder/userfiles/files/patoxipufafuxuni.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16076167db1fc4---1028653398.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/512c7a371f6cef4907acf1a62d14bdb4/13343751500.pdfIn PDF document text
    • https://gk-termopanel.ru/wp-content/plugins/super-forms/uploads/php/files/2d33bd5d095ad074969a5f4b0e6e6e88/31815845533.pdfIn PDF document text
    • http://ecompletecontact.com/ckfinder/userfiles/files/senivefukufadijum.pdfIn PDF document text
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9074019a9---posevow.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/2c221a02762ab0c406b438d7a6b8968d/52111662346.pdfIn PDF document text
    • https://www.parkgest.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160bad68dbcd68---fizesemepiwo.pdfIn PDF document text
    • http://abwninemile.com/uploads/files/14299114251.pdfIn PDF document text
    • http://tuning-zone.eu/userfiles/file/47559307336.pdfIn PDF document text
    • https://paron-rebondir.com/uploads/files/vijula.pdfIn PDF document text
    • http://narcisse.sk/editor_uploads/files/37836073907.pdfIn PDF document text
    • http://karpatskiles.ru/store/files/sipekojalarajapujap.pdfIn PDF document text
    • http://mwflower.com/upimagesfile///mikabatu.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a1633b29ca3---fanipaloboripebewe.pdfIn PDF document text
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/guiitv68cqfhnamljakis6vld0/pubowesebonejopetadun.pdfIn PDF document text
    • http://edwardfmcgintypa.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/zuwikovexafa.pdfIn PDF document text
    • http://powerfalcon.net/uppic/files/kesitalojefodasibinapu.pdfIn PDF document text
    • https://cahayaapi1.com/contents//files/vitiruverofometupino.pdfIn PDF document text
    • https://sharjahcements.com/images/bulk_images/files/gazujevafumiwapumupinupe.pdfIn PDF document text
    • https://olgapopovaphoto.com/wp-content/plugins/super-forms/uploads/php/files/5935d64f83603dda8fd602cb443c262e/68440414432.pdfIn PDF document text
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/51860e3c0869b907b79e80f860908b60/guxijujiveziguvese.pdfIn PDF document text
    • 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_off00010bdf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BDF 19560 bytes
SHA-256: a8f93beaa6c3e0f04886cc5a1e5aecbde3b66ed2925ef3749b6c48733e6e9266
font_01_sfnt_off00013d51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13D51 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015568.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15568 10476 bytes
SHA-256: 3013f1de02afdb980cddeb8fdd9fb485bde4797df3f6d47bde89ce3657448b89