Malicious PDF — malware analysis report

Static analysis result for SHA-256 caee45b4bb67deea…

MALICIOUS

PDF

74.4 KB Created: 2021-09-19 21:30:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: e70cc4855c9b7336351f4a3c3cb6fbcb SHA-1: 0f8f678fb2b8b20de18dca409ccdd7db3e62f532 SHA-256: caee45b4bb67deea2b5515d2b1d51b8fc5b5ae071535dc8b9782ca4174890ab9
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. This script likely redirects the user to a network of external URLs, as indicated by the PDF_SEO_DISPOSABLE_LINK_FARM heuristic and the numerous unknown URLs extracted. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via a link farm.

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
  • 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 https://landbar.com/app/webroot/js/ckfinder/core/connector/upload/files/raguxikoledorapepujo.pdf In PDF document text
    • https://www.savininkai.lt/ckfinder/userfiles/files/tujasuxarurudovowuduvowad.pdfIn PDF document text
    • https://masukpt2.com/contents/files/juwajabeduduzusiwub.pdfIn PDF document text
    • http://studiodelcorso.eu/userfiles/files/26351471979.pdfIn PDF document text
    • http://teaterskolen-efteruddannelsen.dk/ckfinder/userfiles/files/9341569596.pdfIn PDF document text
    • https://euroquimicadistribucion.com/zabaleta/data/imagenes_contenidos/file/18479441402.pdfIn PDF document text
    • http://www.hro.ait.ac.th/js/ckfinder/userfiles/files/34776433293.pdfIn PDF document text
    • https://rtvpuls.com/ckfinder/userfiles/files/fupesesusewebixurolofel.pdfIn PDF document text
    • http://aliancegroup.su/wp-content/plugins/formcraft/file-upload/server/content/files/161312b330046f---41633626445.pdfIn PDF document text
    • http://biblioteka-belzec.pl/upload/files/butikixum.pdfIn PDF document text
    • https://yukkumpulgroup1.com/contents/files/dukigazomup.pdfIn PDF document text
    • https://tutorbolivia.com/userfiles/file/muwoboxuzejudijima.pdfIn PDF document text
    • http://rothemtour.com/FileData/ckfinder/files/20210913_246991352B5B0B9F.pdfIn PDF document text
    • http://www.taxivanclass.com/uploads/ckfinder/files/fipilidejekegisorox.pdfIn PDF document text
    • https://underworldgear.com/upload/users/files/wenilurafipolazosow.pdfIn PDF document text
    • http://www.ruben.pl/ckfinder/userfiles/files/virujubavinivabupo.pdfIn PDF document text
    • http://onlytech-tunisie.com/userfiles/file/59807358651.pdfIn PDF document text
    • http://studiosimonepantaleo.it/userfiles/files/mudinawarugatexudesuko.pdfIn PDF document text
    • http://afro-safari.com/upload/files/59118344593.pdfIn PDF document text
    • http://chrisdepanneservices.fr/Sites/cds/files/99582061063.pdfIn PDF document text
    • https://digireg.cz/upload/56465001818.pdfIn PDF document text
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614374d2a7647---279932054.pdfIn PDF document text
    • https://prcomponents.com/ckfinder/userfiles/files/kelonigunitikofu.pdfIn PDF document text
    • http://harissarantis.com/userfiles/files/94114563673.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=app+for+malayalam+moviesPDF 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_off0000c017.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC017 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d82e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD82E 10476 bytes
SHA-256: 92ec141a477237f92a52f4add88fc409c8bbc15f0937683472fe5d5c83636be4
font_02_sfnt_off0000f009.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF009 17188 bytes
SHA-256: b9aa91ee96505d74fd39b6ed96346d62a121a5da1cb5fb28fd92c1b58f3274c4