Malicious PDF — malware analysis report

Static analysis result for SHA-256 4465a391228c6f61…

MALICIOUS

PDF

71.5 KB Created: 2021-09-18 16:49:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: b5d6711be9b0f454e6dd805365add5ab SHA-1: 83f39f7098f43355e009d3106a56c1b38fc812d8 SHA-256: 4465a391228c6f61d9505e2a9f9a87a3d38dee1f2cb990bcedcb7c09d343cfa6
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was flagged by ML classifiers and ClamAV as malicious, with heuristics indicating embedded JavaScript and external URI redirection. The PDF contains numerous links to external PDF files, suggesting a link farm or redirection mechanism. The embedded JavaScript likely facilitates the redirection to these external resources, which are often used for phishing or to download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://guitarenko.fr/img/files/54311669019.pdf In PDF document text
    • http://savaksangida.com/resimler/files/31082984299.pdfIn PDF document text
    • http://medica-eg.com/userfiles/file/24591148219.pdfIn PDF document text
    • https://gamepinleri.net/calisma2/files/uploads/jizawubewodotiwanaxu.pdfIn PDF document text
    • http://skyrunarser.com/js/fckeditor/editor/filemanager/connectors/php/connector.php/upfiles/file/2109060058308245001bdi1y.pdfIn PDF document text
    • http://babijie.com/upload_fck/file/2021-9-3/20210903050443263808.pdfIn PDF document text
    • https://flyags.com/editorResources/file///jorobidivosuvadoz.pdfIn PDF document text
    • http://drivingschool-brno.eu/files/77960729495.pdfIn PDF document text
    • http://corse.annuaire-regional.com/ckfinder/userfiles/files/zoxetipi.pdfIn PDF document text
    • http://exosportsante.fr/ckfinder/userfiles/files/jizidanikajonubugelitonow.pdfIn PDF document text
    • http://deepakbatteries.com/uploads/file/3872788391.pdfIn PDF document text
    • https://cam-ceeds.org/ckfinder/userfiles/files/jogos.pdfIn PDF document text
    • https://www.info-service.com.tw/plugin/ckeditor/ckfinder/userfiles/files/81164542423.pdfIn PDF document text
    • https://indiansabroad.uk/userfiles/file/rabafodugi.pdfIn PDF document text
    • https://www.ideaklinikbakirkoy.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614319586c693---mezatelulopesipezagoradu.pdfIn PDF document text
    • http://makassitools.com/userfiles/file///66600266671.pdfIn PDF document text
    • http://xn--hy1bt45apoap01a.net/jangheung/userfiles/file/28146659167.pdfIn PDF document text
    • http://aviapartner.biz/js/ckfinder/userfiles/files/46178017937.pdfIn PDF document text
    • https://samirkumarpaul.com/ckfinder/userfiles/files/2591264740.pdfIn PDF document text
    • http://phutungotodungha.com/img/files/febekiwimos.pdfIn PDF document text
    • http://slxiang.com/v15/Upload/file/202198112567275.pdfIn PDF document text
    • http://ancient-theater.gr/media/file/tinugunile.pdfIn PDF document text
    • https://cuatudongsaigon.net/uploads/files/92091263871.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1xuhb7AK25c/uplcv?utm_term=free+gems+on+clash+of+clans+no+surveyPDF link annotation
    • https://bit.ly/3idve6aIn 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_off0000b606.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB606 10852 bytes
SHA-256: b873c769b8c25e8f498bae5ca95d9ad32bb433a76c455c88dbb3fb7af76a1971
font_01_sfnt_off0000ceeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEEB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e6fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6FD 16012 bytes
SHA-256: 458433c7891d58adbf0022ca329256e629220a5f36e575dcc94f3fc36b68c2b9