Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c23458ebe23ffa1…

MALICIOUS

PDF

71.6 KB Created: 2021-09-30 15:20:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 2c15e503bad5f024fdc8ad911dccf252 SHA-1: 7f08f849bf3cc49172273827ff7998a865b5739f SHA-256: 8c23458ebe23ffa1ecdb989327cc2a51f77e380a9fc6690092b0a10a78063135
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external URIs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The embedded JavaScript is likely used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://drafthe.ru/uplcv?utm_term=best+free+screen+recorder+for+android+with+internal+audio PDF link annotation
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/161319ec22201c---41853620354.pdfIn PDF document text
    • http://marienoellebermond.com/img/uploaded/file/pojademedetasekikolal.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/1ogkl0gedseha7he7tdq9cj3i7/95771249271.pdfIn PDF document text
    • https://guptajimarriagebureau.com/userfiles/file/rigeg.pdfIn PDF document text
    • http://blekinge.boj.se/uploads/userfiles/files/fofeduwex.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/161487fa5a565a---vupurolonabi.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/zejibetujuterefuzuzuze.pdfIn PDF document text
    • https://binhvi.com/upload/files/5858786067.pdfIn PDF document text
    • http://xn--80akoseq9f.xn--p1ai/userfiles/file/86233569329.pdfIn PDF document text
    • https://rinducm1.com/contents/files/30960979005.pdfIn PDF document text
    • http://sial.pl/galeria/file/88908138631.pdfIn PDF document text
    • http://xaydunghoangthanh.com/img_duhoc/files/jexapexez.pdfIn PDF document text
    • https://svltv.in/userfiles/files/bupepolulipibujasaweg.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/64605379679.pdfIn PDF document text
    • http://goldenagegroup.vip/userfiles/file/muful.pdfIn PDF document text
    • http://yuha.be/_files/file/59479259529.pdfIn PDF document text
    • http://atya.eu/files/file/pibojaloxolaz.pdfIn PDF document text
    • https://www.vek-bg.com/app/templates/js/ckfinder/userfiles/files/fewerituzerake.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/8iq0g3smb1ko0mrmbe22nt760a/8080804457.pdfIn PDF document text
    • http://riph.pl/userfiles/file/84313328507.pdfIn PDF document text
    • https://liepasmuiza.lv/userfiles/library/11946772125.pdfIn PDF document text
    • http://isdoor.ru/uploads/files/39560172673.pdfIn PDF document text
    • http://nsk-nalogov.net/upload/files/81424885519.pdfIn PDF document text
    • https://easyown.ddproperty.com/datas/files/fivepewiga.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_off0000b479.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB479 10812 bytes
SHA-256: e3a6743fc470d8ef0772bf3f82e20e76d0de9770a9caddc9ffc5ccc05d0aaa7a
font_01_sfnt_off0000cd6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD6E 16728 bytes
SHA-256: 3e4253f59c2ebab2360fa8d85f0f18c1d432b0b3dd15fc3a259c15cfbefb0f29
font_02_sfnt_off0000f823.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF823 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1