Malicious PDF — malware analysis report

Static analysis result for SHA-256 fed399b4fc81a008…

MALICIOUS

PDF

72.6 KB Created: 2021-09-12 14:09:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 8414a3930dbb8bdaff17bce075c88122 SHA-1: 3cc6e12f9aace5471f4878ce1e2253816367d98c SHA-256: fed399b4fc81a008ac50e47e355f8b9e94583732938ddcd1ba40248c00c45b3c
156 Risk Score

Malware Insights

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

The PDF contains a large number of links, many pointing to compromised WordPress sites and disposable domains, which is characteristic of a link farm used for SEO manipulation or distributing malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or distributing malware. The presence of multiple PDF files hosted on these domains suggests a coordinated effort to distribute content through these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://biographiewerkstatt-singer.de/userfiles/file/37824579006.pdf In PDF document text
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c9a6f0e804---6342089586.pdfIn PDF document text
    • http://gz-chengeng.com/uploadfile/files/6086630356.pdfIn PDF document text
    • http://highlevel.pl/userfiles/file/zusoxelug.pdfIn PDF document text
    • http://health-bridge.in/upload/file/22019369668.pdfIn PDF document text
    • http://sensi-leszno.pl/userfiles/file/71884310241.pdfIn PDF document text
    • https://joebalogh.ro/imagini_ws/51946628922.pdfIn PDF document text
    • https://linardi.ru/files/file/66395760701.pdfIn PDF document text
    • http://klusjesindex.nl/images/uploads/dizasifazixarixonin.pdfIn PDF document text
    • https://cdmsig1.com/ckfinder/userfiles/files/5754385310.pdfIn PDF document text
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/r48b00igojjf34ln9nk39fnshk/23141577035.pdfIn PDF document text
    • http://coomargroup.com/ckfinder/userfiles/files/70344447004.pdfIn PDF document text
    • http://zatoodesign.com/userfiles/files/pawatexonifasagibe.pdfIn PDF document text
    • https://devcons.org/uploads/userfiles/files/vawujifabelapopofojexum.pdfIn PDF document text
    • https://niagarablock.com/application/webroot/userfiles/file/madudaluritol.pdfIn PDF document text
    • http://www.gleason.com.au/application/third_party/ckfinder/userfiles/files/73105727537.pdfIn PDF document text
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/b81565ad1e6ad3819d4bdb254af5ffec/3722168391.pdfIn PDF document text
    • http://deeringbayrealestate.com/userfiles/files/57166759106.pdfIn PDF document text
    • http://domgr11.ru/uploads/files/pomorimijokap.pdfIn PDF document text
    • http://haisushitogo.com/uploads/files/puzasodapad.pdfIn PDF document text
    • http://logiccpacma.com/ckfinder/userfiles/files/doteko.pdfIn PDF document text
    • https://pikewallis.no/wp-content/plugins/formcraft/file-upload/server/content/files/1612fec4364369---97586906062.pdfIn PDF document text
    • https://homestayhoian.vn/uploads/image/files/nixeruza.pdfIn PDF document text
    • http://www.tecnologycenter.com/admin/uploaded/fck/file/lamovosepilimix.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=mobile+legends+app+download+for+androidPDF 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_off0000ba04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBA04 10792 bytes
SHA-256: bcf7bc01d91e0f1718acc93cdb1590205fd6e1f83460b8924b9b1aac7abbd1ef
font_01_sfnt_off0000d292.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD292 16472 bytes
SHA-256: ca4f6f74b71886fb50d7bb910c992320577cd6df0c5e3dd15f45209c46d5e1db
font_02_sfnt_off0000fc96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC96 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1