Malicious PDF — malware analysis report

Static analysis result for SHA-256 a77620682f9085eb…

MALICIOUS

PDF

80.6 KB Created: 2021-09-12 18:16:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7418677cd352f7fd2a909d29bffbf248 SHA-1: 5242826f3db377ee1f01ab4715fc7edc7294a65e SHA-256: a77620682f9085ebdac561ed340e2d00c36b1f03244500b96446e41d1091ca83
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent. The primary function appears to be acting as a link farm, directing users to potentially malicious content hosted on compromised or disposable domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/161386e5dc0537---vawipoxeminaduloxofobu.pdf In PDF document text
    • http://serenetour.com/image/upload/File/leguwidawodizif.pdfIn PDF document text
    • https://hasekei.jp/userfiles/file/xelesabavidopukaxes.pdfIn PDF document text
    • https://b2bircruise.travflex.com/bot/ckfinder/uf/files/gipavewasijubonegukizojaz.pdfIn PDF document text
    • http://www.almansori-ye.com/almansorifiles/files/5545522967.pdfIn PDF document text
    • http://hightopeducation.com/cms_uploaded/file/84245256839.pdfIn PDF document text
    • http://benetworkingpro.com/ckfinder/userfiles/files/45040307839.pdfIn PDF document text
    • https://agriplan-rs.com/dados/ckfinder/files/76903737960.pdfIn PDF document text
    • http://beccaro.it/userfiles/files/13913085523.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/1612f889d6e3cc---pofatizepafepigoxak.pdfIn PDF document text
    • http://eco-building.cz/UserFiles/File/57338721327.pdfIn PDF document text
    • https://tonymusic.se/UserFiles/files/65873506639.pdfIn PDF document text
    • http://alpes-maritimes.proximeo.com/ckfinder/userfiles/files/7490730054.pdfIn PDF document text
    • https://projetovm.com/uploads/files/31603506199.pdfIn PDF document text
    • https://www.la-melodie-des-saveurs.fr/ckfinder/userfiles/files/judixisuxerajuwevo.pdfIn PDF document text
    • http://baiduvpn.com/upload/files/gagarawon.pdfIn PDF document text
    • http://brmhn.com/userfiles/file/20210906232931_d0ezo2.pdfIn PDF document text
    • http://rilta.net/userfiles/files/62271018845.pdfIn PDF document text
    • https://www.grandiosa.is/wp-content/plugins/super-forms/uploads/php/files/9cbbf0khprvedm6llu76f03vp2/lavepilip.pdfIn PDF document text
    • http://trainternational.in/wp-content/plugins/formcraft/file-upload/server/content/files/1613c21802cf9c---42157014361.pdfIn PDF document text
    • http://picart-personal.pl/fckupload/upload/file/86564307906.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=mi+lock+patternPDF 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_off0000d92b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD92B 10284 bytes
SHA-256: 2bfc3acc17dcda6e1fcc8a93355ededf9277ad360343e729871adc58cf3a4995
font_01_sfnt_off0000f06a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF06A 17528 bytes
SHA-256: c66541eeeefb903d6cfc55f369a6d00efbd98498f2a114aa8ebc86b524c591ae
font_02_sfnt_off00011d52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D52 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1