Malicious PDF — malware analysis report

Static analysis result for SHA-256 31c00ca51ca128b4…

MALICIOUS

PDF

69.1 KB Created: 2021-10-02 14:30:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: cba60c42c6c7ea76e5dbbe7de636b668 SHA-1: b15a85b718823f9b5d4bea5ca266fcfd105b40de SHA-256: 31c00ca51ca128b49f3a31eff9db48fcc77854d8fdb020ceadc0897b50f3917a
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and a large number of external URIs, many hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing sites or download further malware. The embedded JavaScript is likely used to facilitate these redirects or obfuscate the malicious links.

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 https://allytemp.ru/uplcv?utm_term=legend+definition+geography PDF link annotation
    • http://maezawa-jidousha.com/js/upload/files/19662464895.pdfIn PDF document text
    • https://bjjewels.net/nbloom/fckuploads/file/nowidujutipogizaluzupameb.pdfIn PDF document text
    • http://marmaraisg.com/images_upload/files/kukiketagufizapigegekaj.pdfIn PDF document text
    • http://zrdb-drogbud.pl/Upload/file/9415448808.pdfIn PDF document text
    • http://presssimayeshahr.ir/pic/file/17424436065.pdfIn PDF document text
    • http://cableesmaltado.com/d/files/58562290201.pdfIn PDF document text
    • https://editions-tlp.fr/ckfinder/userfiles/files/64178284873.pdfIn PDF document text
    • http://kolaykanal.com/userfiles/files/xanigerotegigali.pdfIn PDF document text
    • http://manvilastrust-org.bvirani.com/ckfinder/userfiles/files/rilixuzuvupolakadifok.pdfIn PDF document text
    • http://asr-net.ru/uploads/files/junafovi.pdfIn PDF document text
    • http://synthecinter.com/userfiles/files/nurunavunatuxozoxilikusaj.pdfIn PDF document text
    • https://drinkpoint.com/uploads/files/45033327752.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16156719d200af---82299125104.pdfIn PDF document text
    • https://arrayamed.com/userfiles/file/43107092027.pdfIn PDF document text
    • https://kasihpaham.com/contents/files/7669060936.pdfIn PDF document text
    • https://darshanam.com/ckfinder/userfiles/files/90712371073.pdfIn PDF document text
    • http://dobrejaja.com/Upload/file/gizewalagezupukos.pdfIn PDF document text
    • https://tfpac.com/nbloom/fckuploads/file/16341992685.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614da37640629.pdfIn PDF document text
    • https://solidpractise.com/files/userfiles/file/mipujevapetijuximijokoj.pdfIn PDF document text
    • http://gianphoiduyloimodel.com/Images_upload/files/larumolibisexa.pdfIn PDF document text
    • https://groupekheidri.com/ckfinder/userfiles/files/67618053670.pdfIn PDF document text
    • https://seedomoretravel.com/files/files/16765729397.pdfIn 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_off0000b0cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB0CD 14992 bytes
SHA-256: ee275adc617abcc762daeb21d5b0c1da9b3ee5a1f73e34dbf20410e0e8464b6a
font_01_sfnt_off0000d690.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD690 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000eea7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEA7 10636 bytes
SHA-256: 0ea829ce5b9c087fa28dcb099fb822977e127e00b22369d9ff8e2c220273d213