Malicious PDF — malware analysis report

Static analysis result for SHA-256 823b39d51a58d1f9…

MALICIOUS

PDF

81.7 KB Created: 2021-09-09 01:49:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: fd225e9fc96293f762b78fc56d68e088 SHA-1: 05992b39012cc4521b053c3dd639be30aeb7b833 SHA-256: 823b39d51a58d1f9aa4d69a44381dbc1074e862057d9b83b98258b7524d219a9
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. The presence of numerous external URIs, many pointing to PDF files on potentially disposable hosting, suggests a link farm or redirection mechanism. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious sites or download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://vimar.ua/userfiles/files/zudosazumotulosijap.pdf In PDF document text
    • http://flemingdecal.com/uploads/assets/file/galodarig.pdfIn PDF document text
    • http://lamarchesainterita.be/lamarchesainterita/imgdb/news/files/76329662147.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/161370b44e3612---49082812866.pdfIn PDF document text
    • https://habibitoursegypt.com/ckfinder/userfiles/files/73386478440.pdfIn PDF document text
    • https://cliniquemyo.com/userfiles/file/84793671115.pdfIn PDF document text
    • http://ouhkpthaa.org/userfiles/jizafazum.pdfIn PDF document text
    • http://flagrant-desir.com/userfiles/file/72766617684.pdfIn PDF document text
    • http://www.afurg.com.br/assets/ckfinder/userfiles/files/mumakukezil.pdfIn PDF document text
    • http://lavera.it/wp-content/plugins/formcraft/file-upload/server/content/files/1613927ddbdd7f---pejimikokapar.pdfIn PDF document text
    • http://joltiy.ru/uploads/files/balogujujida.pdfIn PDF document text
    • https://atlas-consulting.ro/fckeditor/fisiere/file/fivofodelijokowukejix.pdfIn PDF document text
    • http://tiramisu-o.com/yamituki-n/uploads/files/murojenige.pdfIn PDF document text
    • http://ammk.sk/userfiles/file/39921330392.pdfIn PDF document text
    • http://only-svet.ru/upload/files/88027144576.pdfIn PDF document text
    • https://mimpi1pusat.com/contents/files/kivaximizeta.pdfIn PDF document text
    • http://megaprestige.ru/uploads/files/7409468811.pdfIn PDF document text
    • http://fw-simple.com/uploads/files/92241119167.pdfIn PDF document text
    • http://bluestandard.pl/ckfinder/userfiles/files/97194038451.pdfIn PDF document text
    • https://alcoolassistance-creuse.net/www/site/js/ckfinder/userfiles/files/52666998830.pdfIn PDF document text
    • https://xeroxexpres.cz/userfiles/file/zogorolupefotoxosi.pdfIn PDF document text
    • http://mishelik.ru/userfiles/file/napujabibupokojuki.pdfIn PDF document text
    • http://architettoangeli.it/userfiles/files/74851203965.pdfIn PDF document text
    • http://ozcetinler.com/userfiles/file/62590781223.pdfIn PDF document text
    • https://thietkewebseo.com/webroot/img/files/14072430980.pdfIn PDF document text
    • https://henseltech.cz/userfiles/file/zabelezuwusadeber.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=dream+league+19+hacked+apkPDF 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_off0000db45.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB45 10792 bytes
SHA-256: e7fe88a463c246c081cd63e4d2f31acd566a646476e36e8402ae20e02843d305
font_01_sfnt_off0000f3fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3FC 17456 bytes
SHA-256: 42ddd464f189ee76bb4a2fd664f1aeeb364cc9c967dbe1d16408146438c8a3ca
font_02_sfnt_off00012160.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12160 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1