Malicious PDF — malware analysis report

Static analysis result for SHA-256 dcea934ef33bede3…

MALICIOUS

PDF

84.9 KB Created: 2021-09-21 04:45:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 4fb18933b87b5f1fd45e07a0bd9f2176 SHA-1: 8cccabd0cf3c817f62255a7b114815867fe24cb4 SHA-256: dcea934ef33bede3124625bda42ec43252e1ec8f6ed2a38264e1e84e28f22d4a
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript and a large number of external URIs, many of which point to disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. The embedded JavaScript is a common technique for exploiting PDF vulnerabilities or redirecting users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Malformed active-content stream length medium PDF_MALFORMED_EXPLOIT_STREAM_LENGTH
    A PDF stream that carries active/exploit-looking content has a declared /Length that does not match the recovered stream body. Malformed stream boundaries and length mismatches are common parser-evasion/supporting evidence around Reader exploit streams.
  • 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://fc-junajted.com/upload/datoteke/kobagavur.pdf In PDF document text
    • https://hkpefa.org/editor_upload/file/86244138319.pdfIn PDF document text
    • http://studioarchoggianiepartners.it/userfiles/files/seluxipebeve.pdfIn PDF document text
    • https://textosolutionslinguistiques.ca/upload/editor/file/59265549063.pdfIn PDF document text
    • https://fertilizerproductionprocess.com/d/files/12949370029.pdfIn PDF document text
    • http://agriturismoilnoceto.com/userfiles/files/tezokizawerosi.pdfIn PDF document text
    • https://bepcongnghiepphuchung.vn/userfiles/file/mofofezosufo.pdfIn PDF document text
    • https://hylyt.co/wp-content/plugins/super-forms/uploads/php/files/c76ee1ee8e631463c3f3e25b7d557edb/tonetafatevit.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/48b399cc0c06d135f35c6c079ae076e0/73961205563.pdfIn PDF document text
    • http://tko.wavedev.net/img/files/files/woxagoroveme.pdfIn PDF document text
    • https://quimicasorocolor.com.ve/ckfinder/userfiles/files/13850339037.pdfIn PDF document text
    • http://augustaelectricalwork.com/editorData/file/faminatilug.pdfIn PDF document text
    • http://ventilatoryzlin.cz/images/file/valiwedowuvogutasa.pdfIn PDF document text
    • http://autosvanbeek.nl/mindcms/js/ckf/userfiles/files/73868083475.pdfIn PDF document text
    • https://giridhareye.org/ckfinder/userfiles/files/99973117008.pdfIn PDF document text
    • https://nezamirekhaseafoods.com/userfiles/file/rosatepezudejagobababofal.pdfIn PDF document text
    • http://garageanything.com/js/upload/files/nanojikev.pdfIn PDF document text
    • https://zemiigori.com/uploads/file/vifidubugupanifezezabino.pdfIn PDF document text
    • https://ostrichtours.com/ckfinder/userfiles/files/jonipebifavaw.pdfIn PDF document text
    • http://physocare.com/Images_upload/files/60553195684.pdfIn PDF document text
    • http://csc0898.com/userfiles/file/20210919180455_88ydnd.pdfIn PDF document text
    • http://icloudcleaners.com/uploads/account/autoresponderfiles/23137973597.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3vuEKuznOb8/uplcv?utm_term=android+application+documentationPDF 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_off0000e727.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE727 17708 bytes
SHA-256: 0516acc1545fca56596d96af9917a55e27aa90fe354afab40f161eef5d23ef41
font_01_sfnt_off00011574.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11574 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012d8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D8B 10588 bytes
SHA-256: 4c973540e6457006659a71b4bc34dc4d831524635a04ab422343d53fba1277e3