Malicious PDF — malware analysis report

Static analysis result for SHA-256 c38e6c46ad272841…

MALICIOUS

PDF

78.3 KB Created: 2021-09-09 06:58:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 5dae3c78142769a7dadc8a5f7270f8c1 SHA-1: 757b4107f04bfd88950dbb5c76b6900e72aae981 SHA-256: c38e6c46ad272841d3060b44469c21bac10813ef95d88ae14a6f9d99780977e2
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by multiple heuristics, including a critical ClamAV detection and an ML classifier, indicating malicious intent. The presence of embedded JavaScript (PDF_JS) suggests an attempt to execute code, likely to download and run a secondary payload. The PDF also contains numerous external URIs, with one pointing to a link farm, potentially used for obfuscation or redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • 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 http://e-district.org/userfiles/file/tadirunu.pdf In PDF document text
    • http://www.dialog-seversk.ru/jsplugins/ckfinder/userfiles/files/gurubuvoxaxi.pdfIn PDF document text
    • http://flynewsletter.com/uploads/file/jirakijalobegem.pdfIn PDF document text
    • http://vanharteyoga.nl/uploads/files/28892736103.pdfIn PDF document text
    • https://tsydesign.com/userfiles/jws/files/buxebuli.pdfIn PDF document text
    • https://skl.deindrukdemo.nl/upload/files/poxozalidizeliwojijulo.pdfIn PDF document text
    • http://www.herbertvanderbrugghen.nl/draft/28325273867.pdfIn PDF document text
    • https://berettyotv.hu/userfiles/files/63276891155.pdfIn PDF document text
    • http://mbjarrahi.com/UploadedFiles/New/file/fasabezazagozovulebarolir.pdfIn PDF document text
    • http://kurumakaitori-one.com/js/upload/files/60979619603.pdfIn PDF document text
    • http://hbaoge.com/upload/files/nepowilawukusoga.pdfIn PDF document text
    • http://heaig.org/editor/ckfinder/userfiles/files/jatanuzapupel.pdfIn PDF document text
    • http://greenhere.cn/upload/ckimg/files/202109081638436527.pdfIn PDF document text
    • http://spad.kr/userData/ebizro_board/file/64910095575.pdfIn PDF document text
    • https://matras-matrasych96.ru/admin/ckfinder/userfiles/files/sijuvulunopabovugi.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1613357addc710---zusutawiwozemudifin.pdfIn PDF document text
    • http://studiolaviano.it/userfiles/files/zidizapiluvaxa.pdfIn PDF document text
    • http://careerpathrecruitment.com/swapscan/app/webroot/js/ckfinder/userfiles/files/gabagarali.pdfIn PDF document text
    • http://vibrobeton.by/pics/files/tadamut.pdfIn PDF document text
    • http://csc0535.com/userfiles/file/20210908210755_4t639e.pdfIn PDF document text
    • https://mut-zur-veraenderung-hambuch.de/userfiles/file/79266122186.pdfIn PDF document text
    • https://honkakuji.jp/honkakuji/images/ckfinder/files/bukatiwokomikevewo.pdfIn PDF document text
    • http://interfacetravels.com/app/webroot/js/ckfinder/userfiles/files/82418870802.pdfIn PDF document text
    • https://sabagdasarov.ru/upload/file/titotovokabajajomis.pdfIn PDF document text
    • https://monyetjoget.com/contents/files/gamudomudawugexuxisebe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=2+bedroom+house+floor+plan+design+3dPDF 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_off0000cc40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC40 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e457.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE457 11284 bytes
SHA-256: 23b8cfb29d02878d4474393152e0788b2e5017da497fa231c7a11865d27c0cc1
font_02_sfnt_off0000fe36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE36 17388 bytes
SHA-256: 035525fa946a3ab391640a4449c5641fa8c70fe43dfb9e475ae82262c9c87450