Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7d1d294b8cc95ac…

MALICIOUS

PDF

84.1 KB Created: 2021-09-07 06:00:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-02
MD5: cd556e6edab8a1dec194b9b210e9d087 SHA-1: 8a498718401d93dc2ebdb818bd8ff78b8b6c26c4 SHA-256: b7d1d294b8cc95ac40446e103f9301d23e94d88c6ea2c941d68b12825b767c9e
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://crewmak.ru/uplcv?utm_term=rrb+ntpc+general+science+syllabus+pdf PDF link annotation
    • http://specimport.by/files/files/biliraxo.pdfIn PDF document text
    • http://keralabiblesociety.com/fck_uploads/file/96924029302.pdfIn PDF document text
    • http://telmeed.com/web/ckfinder/userfiles/files/69875330045.pdfIn PDF document text
    • https://techson-cctv.com/upload/file/zesizemamadaloguwif.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/53917595a9ab56670062636d0211044b/32580905296.pdfIn PDF document text
    • http://harlit.com/ckfinder/userfiles/files/20210709_214733.pdfIn PDF document text
    • http://aostavet.it/userfiles/files/84940616792.pdfIn PDF document text
    • https://sgcaregiver.org/contents/files/76512348582.pdfIn PDF document text
    • http://quickvideo.nl/userfiles/file/batutidetofalezizabi.pdfIn PDF document text
    • http://amuseonline.com/absite/userfiles/file/83281786225.pdfIn PDF document text
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fea33d8db0---pokebafalili.pdfIn PDF document text
    • http://geobigoni.it/userfiles/files/novotezanivujudifavevebo.pdfIn PDF document text
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/a892105beab029776ee98eaf2153c23b/xukuzajape.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b340275df92---18083973089.pdfIn PDF document text
    • http://aldo-ins.com/userfiles/file/79307979821.pdfIn PDF document text
    • http://pomocnaukowa.net/Upload/file/lopakelobezige.pdfIn PDF document text
    • https://manualismedicina.hu/fileok/file/4189504785.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16098405fb69a3---derisibokotopigizebasib.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/20156639855.pdfIn PDF document text
    • http://svx.su/ffile/file/duvizagovagudopasijesovi.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad303bcb8e4---78563435760.pdfIn PDF document text
    • https://shining4u.com/wp-content/plugins/super-forms/uploads/php/files/c3d4a51f2e94139af7d61ce617b649f3/12833246451.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_off0000e398.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE398 11072 bytes
SHA-256: 4d14abc07725557708e235d54e6ffb33f5c83db671b6522517d6d5b577646607
font_01_sfnt_off0000fd1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD1E 17632 bytes
SHA-256: 1be4629a1152a4d189eaf504a617ceed2ee9ee45355b096a5a928ac5512f1314
font_02_sfnt_off00012aa8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12AA8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1