Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a64834ce423bf24…

MALICIOUS

PDF

72.8 KB Created: 2021-10-03 00:33:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: c2ffca3b613e5b764e5788ddb5b55a24 SHA-1: 1c75dbf6e6f3caba4b0c65921b7def44bf314b8c SHA-256: 4a64834ce423bf247310288c6a1cc5cdbbc9d84700cf727f4e63930eb0a8bfe2
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URLs, many of which are hosted on disposable domains and appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and numerous embedded URLs suggest it is designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://laborke.ru/uplcv?utm_term=henderson+track+and+field PDF link annotation
    • https://hankilfood.com/userfiles/file/20210929205143.pdfIn PDF document text
    • http://www.pranabkumar.com/fckimages/file/mazemolawemasedipumuz.pdfIn PDF document text
    • http://thibangoto.com/app/webroot/uploads/files/xorobixesaxawoniboso.pdfIn PDF document text
    • https://miamivanservice.net/wp-content/plugins/formcraft/file-upload/server/content/files/1614d25c291115---24120129977.pdfIn PDF document text
    • http://tatugigo.com/ckfinder/userfiles/files/48955720766.pdfIn PDF document text
    • http://studiodrago.eu/userfiles/files/pogopovapujirakalon.pdfIn PDF document text
    • http://apothepharma.com/upload/files/11739529620.pdfIn PDF document text
    • http://haphadoor.com/upload/files/tirazazisev.pdfIn PDF document text
    • https://optical-axis.com/uploads/files/202109041732504238.pdfIn PDF document text
    • https://alasclub.gr/neuro/ckfinder/userfiles/files/89761919279.pdfIn PDF document text
    • http://cosmeticdermatologymiamibeach.com/uploads/data/files/85801606685.pdfIn PDF document text
    • http://93564497.com/userfiles/sufonawezivedirazepuzibe.pdfIn PDF document text
    • http://tverzhilservis.ru/foktver.ru/ckfinder/userfiles/files/19699875662.pdfIn PDF document text
    • https://aarushimukhwas.idealviews.com/userfiles/files/zidanavawot.pdfIn PDF document text
    • https://jooli.ru/ckfinder/userfiles/files/xosurefakapesabozagemuv.pdfIn PDF document text
    • http://geoscan.it/userfiles/files/3206874110.pdfIn PDF document text
    • http://flooroverstock.com/admin/userfiles/file/lodilijobesu.pdfIn PDF document text
    • http://skidubravy.sk/spravca/ckfinder/userfiles/files/jimakifa.pdfIn PDF document text
    • http://www.prakashirrigation.com/uploads/fck/files/46317757079.pdfIn PDF document text
    • https://numen-wow.com/userfiles/cloud/files/wawurovimuvovepixod.pdfIn PDF document text
    • http://www.truca-taoules.com/ckfinder/userfiles/files/pomudavebulamafubasaju.pdfIn PDF document text
    • http://mottaing.eu/userfiles/files/vegajezekutefafu.pdfIn PDF document text
    • http://aromamahabaleshwar.com/ckfinder/userfiles/files/90405910516.pdfIn PDF document text
    • http://okna-dvere-online.cz/media/upload/upload/file/xotezopobekifi.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_off0000b656.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB656 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ce68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE68 18288 bytes
SHA-256: 7ed80cdbf48fd810c0ead2fbf53cf377debc47e7a4c999a536721e1928dab6f4
font_02_sfnt_off0000fd62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD62 10552 bytes
SHA-256: 031e009e5d26f70418779f815c584e93ec220d4641333bba50b391476cdf708e