Malicious PDF — malware analysis report

Static analysis result for SHA-256 7d835d6973ceaa7c…

MALICIOUS

PDF

69.6 KB Created: 2021-10-01 10:27:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: a95cef8d0043cd8aca4b37ab0a164cae SHA-1: 8f6b33f4d415865dac1f7eac300e46b713b99295 SHA-256: 7d835d6973ceaa7ce3612bcc5a11a663b6f7fcf615ede7c4800e1e43f6bdfeb1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, with heuristics indicating it functions as a link farm. Multiple URLs point to compromised CMS uploads and disposable hosting, suggesting an attempt to redirect users to malicious content. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of a phishing or malware distribution attempt, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://www.ideaklinikkadikoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/161314c6aa5c1f---wibewadi.pdf In PDF document text
    • https://partroyfuneralhome.com/partroy/assets/file/23407612696.pdfIn PDF document text
    • https://shinaltd.ru/images/file/pefilemona.pdfIn PDF document text
    • http://khacvietlaser.vn/public/images_news/files/83687686180.pdfIn PDF document text
    • http://otelm4b.ru/admin/ckfinder/userfiles/files/juzokejosif.pdfIn PDF document text
    • https://legyenegyjonapod.hu/userfiles/files/gegakudogojefag.pdfIn PDF document text
    • http://www.libroparlatolions.it/backoffice/ckfinder/userfiles/files/27057463465.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16140849f7f4b8---70066995755.pdfIn PDF document text
    • http://mistral-paints.cz/userfiles/files/57246266871.pdfIn PDF document text
    • http://jinyezi.cn/upload/51584437961.pdfIn PDF document text
    • https://ordermorestuff.com/cmsCart/upload/file/61814524225.pdfIn PDF document text
    • https://jensbrode.de/files/file/ribifitatosalaxogu.pdfIn PDF document text
    • https://www.tonygssoulfood.com/wp-content/plugins/super-forms/uploads/php/files/c73567944abb930d4219700b94ef3038/45613603626.pdfIn PDF document text
    • http://losmarinoslanzarote.com/marinarubicon/admin/file/pemuwosogiwazudedoromok.pdfIn PDF document text
    • http://dientrotiendathc.com/media/ftp/file/gulapojig.pdfIn PDF document text
    • https://resulgame.com/calisma2/files/uploads/jakegolimemazin.pdfIn PDF document text
    • http://uniroll.pl/user_images/file/regakitu.pdfIn PDF document text
    • https://cubic.is/userfiles/file/73266819063.pdfIn PDF document text
    • https://kanat.com/upload/ckfinder/files/sevanumojijukisidikimi.pdfIn PDF document text
    • https://receptabc.hu/images_banner/files/pevoziferagibamep.pdfIn PDF document text
    • http://adveotec.com/img/file/16222778495.pdfIn PDF document text
    • https://xn--z4qq44i.tw/upload/actfiles/27286703974.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=search+in+android+examplePDF 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_off0000b14c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB14C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c963.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC963 10692 bytes
SHA-256: 0956b90a1753eba0f6da5980dd70ae668966c15bcab5de6fb1b3f401653f1ede
font_02_sfnt_off0000e19d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE19D 15340 bytes
SHA-256: d6862c564c4fa2fc322637b3db3a8409f6ab2968411aae8b1b969b79f106b421