Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c9134d8e5347e89…

MALICIOUS

PDF

105.5 KB Created: 2021-09-08 02:16:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: f9d4178e385c6cda9115618fdfddaaff SHA-1: 416d70f55a5cc9e0e0aef42d03f311f4abe700f4 SHA-256: 1c9134d8e5347e8974a49dd1fafb798afa49a0dd9425370551a68ba7e6cb4b78
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file containing embedded JavaScript, which is a common technique for delivering malicious content. Heuristics indicate that the PDF hosts a link farm pointing to compromised WordPress upload storage and disposable hosting, suggesting an attempt to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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 https://standsimulator.com/ckfinder/userfiles/files/46829855732.pdf In PDF document text
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aaf67eed279---90734649189.pdfIn PDF document text
    • https://prana.video/wp-content/plugins/super-forms/uploads/php/files/3op605s0vci87ujica92pdd9gq/zidewedavokis.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a847957235a---ponogixixideg.pdfIn PDF document text
    • http://zhhyhb.com/uploadfiles/files/33191170.pdfIn PDF document text
    • https://monacollection.ua/wp-content/plugins/super-forms/uploads/php/files/83c552e13adb4cd49c3503a0d1ec6475/70902027575.pdfIn PDF document text
    • http://sentai.cc/data/file/20210904_085502_691.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070c7b50e17f---mibawok.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b92aeb00aa---julasepogimajejusi.pdfIn PDF document text
    • http://www.orhancoskun.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606db2661baa0---47238795102.pdfIn PDF document text
    • http://asesoriagarpe.com/wp-content/plugins/formcraft/file-upload/server/content/files/161121687549cb---34454946717.pdfIn PDF document text
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/6e99e0b235a6071be3a4255b9c479a52/12382366248.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/16130218e9796f---tumiwepetikoj.pdfIn PDF document text
    • http://carnow.jp/js/upload/files/33329038485.pdfIn PDF document text
    • https://isagrinio.gr/userfiles/19227491579.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606d3610185d7---44616141363.pdfIn PDF document text
    • http://kaitosushisb.com/uploads/files/77568026170.pdfIn PDF document text
    • http://www.onekaddy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f88384092b3---zisolatixixar.pdfIn PDF document text
    • http://preserveproperties.com/userfiles/files/nizafuvojipol.pdfIn PDF document text
    • http://orthodoxvaidikasanghom.org/userfiles/file/gijokanadefokesoti.pdfIn PDF document text
    • https://vinisfarm.com/wp-content/plugins/super-forms/uploads/php/files/a2d6fa480d70ecf1ae05ae89a6c6c6f6/5777413596.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b78b54e0fb0---96078137294.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=rote+liste+gef%C3%A4hrdeter+tiere+pflanzen+und+pilze+deutschlands+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_off00012d51.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D51 11360 bytes
SHA-256: a1231272faf7c7017e0bf0a92eeb7641c2f6aee0f5d70212ff81fe1fb87c4cb9
font_01_sfnt_off0001475f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1475F 20956 bytes
SHA-256: 93e21c489d1b609a2fc9883929ee6ef15dc8567273ea312af09f5302e099286b
font_02_sfnt_off00017c8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17C8A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1