Malicious PDF — malware analysis report

Static analysis result for SHA-256 c67a72961637c352…

MALICIOUS

PDF

80.6 KB Created: 2021-09-20 17:48:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 5996265e26eefa556086890318c9f528 SHA-1: c73f8322a75e29a1ee810d3b4585ae6b4d9683d4 SHA-256: c67a72961637c352955ad687c59a91e1a660b7b092c43950bce023a9b8699db2
74 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, which is a common technique for executing malicious code. The presence of numerous disposable links and a redirector in the URL structure, combined with the ML classifier's high confidence, suggests a malicious intent to distribute further payloads or phish for information. The document body is heavily obfuscated and unreadable, but the heuristics indicate a link farm designed to obscure the true destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 5

  • 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://talleresjpg.es/img/file/13385590532.pdf In PDF document text
    • http://7166867.ru/ckfinder/userfiles/files/49091916939.pdfIn PDF document text
    • https://citronixdeflection.com/nbloom/fckuploads/file/93884786424.pdfIn PDF document text
    • http://docando.es/js/ckfinder/userfiles/files/tiwivavitamuvoguvutovomaw.pdfIn PDF document text
    • http://goodtraefarm.com/ckupload/files/48893039752.pdfIn PDF document text
    • http://assessmentinsight.com/ckfinder/userfiles/files/solakimigovukute.pdfIn PDF document text
    • http://paroissedementon.fr/upload/files/dunefurovanogab.pdfIn PDF document text
    • http://isdoor.ru/uploads/files/zunop.pdfIn PDF document text
    • http://aodaibooking.com/FileData/ckfinder/files/20210910_F1157D27A15AFAC2.pdfIn PDF document text
    • http://epodhajska.eu/UserFiles/File/mugenanosixijepe.pdfIn PDF document text
    • http://spl-designs.com/ckfinder/userfiles/files/texuzosebe.pdfIn PDF document text
    • http://h-n-s.net/userfiles/file/joginigafuwiwegotodum.pdfIn PDF document text
    • http://maszyny.pl/userfiles/file/romesevogejokovuxetig.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/a8ie1f3neb23r4fum5mol6nfs0/55041175395.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/1613a1ed21293f---wugeladano.pdfIn PDF document text
    • https://manage4.realtourvision.com/rtv/ckfinder/userfiles/images/files/leradoganonofapene.pdfIn PDF document text
    • https://krassimirtaskov.com/userfiles/files/90239385165.pdfIn PDF document text
    • http://smalternatywa.pl/media/upload/files/295c2b578b27610848bf9459cf770e28.pdfIn PDF document text
    • https://liho.cz/UserFiles/File/zopijofumisiwarujifafaj.pdfIn PDF document text
    • http://physocare.com/Images_upload/files/33385114976.pdfIn PDF document text
    • http://milwaukee.center/userfiles/file/zidotasofe.pdfIn PDF document text
    • https://crc.creativechange.net/ckfinder/userfiles/files/kenepakaguxodoradabas.pdfIn PDF document text
    • https://heatingboiler.ca/fck_upload/file/63812499288.pdfIn PDF document text
    • https://101doctor.com/uploads/ckfiles/files/613988de3f79c.pdfIn PDF document text
    • http://adhunikjewellers.com/ckfinder/userfiles/files/dedugugutidufiwor.pdfIn PDF document text
    • http://oresteruggiero.com/userfiles/files/12417610101.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=ccna+study+guide+pdf+2019PDF 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_off0000d3cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3CC 11236 bytes
SHA-256: 254b8b02d758216060c9bc987cd1e7a32c897510db53ee0b9fd9934ab7c6b29e
font_01_sfnt_off0000ee3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE3C 18072 bytes
SHA-256: e0c9e5db2765ebf01d42eed1d9594ff76cadc713edc3bbc0e9431b671c9b2cc4
font_02_sfnt_off00011cdc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CDC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1