Malicious PDF — malware analysis report

Static analysis result for SHA-256 08f23755607a7f96…

MALICIOUS

PDF

76.2 KB Created: 2021-09-11 09:11:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: d48c6c08321397e97e4bdab7968e2ba2 SHA-1: d2fdf9467c5a3e3a6f8ab706fa0af827d2b55cc4 SHA-256: 08f23755607a7f96ff556dc6ca071c0f918c005202005d4d3d0657d088228439
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and a machine learning classifier. It contains embedded JavaScript and numerous links pointing to compromised websites, suggesting an attempt to redirect users to malicious content. The presence of a link farm on disposable hosting further indicates a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://queure.ru/uplcv?utm_term=machine+learning+using+matlab+pdf PDF link annotation
    • http://www.communityheroesproject.org/wp-content/plugins/formcraft/file-upload/server/content/files/16138e139c0afd---rigesimujunuruninu.pdfIn PDF document text
    • http://mmbassisiprovince.in/files/js/ckfinder/userfiles/files/zojali.pdfIn PDF document text
    • https://mallarpurnaisuva.org/go/file/sivuluwuretozokiwesasoj.pdfIn PDF document text
    • http://topenglish.sk/app/webroot/gallery/files/patomedigojewifabijisuvu.pdfIn PDF document text
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16139596437efb---3187813005.pdfIn PDF document text
    • http://hunicorn.hu/userfiles/file/rabizutasu.pdfIn PDF document text
    • http://ohmytour.kr/FileData/ckfinder/files/20210901_6C48FCA71622180A.pdfIn PDF document text
    • http://benthanhsgfarm.net/images/uploads/files/91075717040.pdfIn PDF document text
    • https://www.groupe-coelho.fr/ckfinder/userfiles/files/doxobalakuvisunuf.pdfIn PDF document text
    • http://badischer-kunstverein.de/ckfinder/userfiles/files/62460994015.pdfIn PDF document text
    • https://stauber.lt/images/files/dedufelenofabut.pdfIn PDF document text
    • http://a-pro-peau.fr/userfiles/file/88990341056.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613c05b28f22d---29635694623.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/1d0723c33cba018043c4ce7214264c35/58301347100.pdfIn PDF document text
    • http://canigrup.com/userfiles/file/masak.pdfIn PDF document text
    • http://canyonoaksmtg.com/~duckdi5/canyonoaksmtg.com/content/file/61802725237.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/161341258c5ab1---23428338749.pdfIn PDF document text
    • http://laarakkers.com/ckfinder/userfiles/files/60029134768.pdfIn PDF document text
    • http://webinaris.blog/ckfinder/userfiles/publics/files/76588876579.pdfIn PDF document text
    • http://emannsltd.com/userfiles/11330524477.pdfIn PDF document text
    • http://michael-dhom.com/webseiten/file/56478723463.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_off0000c5bd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5BD 17220 bytes
SHA-256: a51683d86ca04a11d86dfb6a97420e0b89ad3c3c1e9839c652c89dfdc328bf61
font_01_sfnt_off0000f21a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF21A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010a31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A31 11180 bytes
SHA-256: 5bf6925880681b777d98cdeff5e6e0787b0e14584eaf1ace61691cff64636d98