Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8d4a4acf6f3aa79…

MALICIOUS

PDF

75.0 KB Created: 2021-09-28 09:49:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7178cbd5e1210056ef4875d2c4e18829 SHA-1: 343fd4bb4e811407a46a2e7c65e7ec2d87d7ed4e SHA-256: b8d4a4acf6f3aa795b2ab8e8867e6556e1767aee371136336f78b1a07fd6a157
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to disposable hosting, indicative of a link farm designed to redirect users to malicious content. ClamAV detection and ML classification strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URIs are consistent with techniques used to deliver second-stage payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • 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.
  • 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://philabc.ru/uplcv?utm_term=juegos+para+motorola+android+gratis PDF link annotation
    • http://reversetheclocknow.com/ckfinder/userfiles/files/89281708643.pdfIn PDF document text
    • https://kamhosting.nl/ckfinder/userfiles/files/tipepokakun.pdfIn PDF document text
    • https://www.karelo.com/uploads/File/81238631873.pdfIn PDF document text
    • http://reguitti-engineering.it/userfiles/files/97420140999.pdfIn PDF document text
    • https://ngenadmin2.nextgenphotosolutions-beta.com/app/webroot/files/file/97923500269.pdfIn PDF document text
    • https://solener.info/ckfinder/userfiles/files/33939103937.pdfIn PDF document text
    • http://chiaranannini.com/userfiles/files/15791626403.pdfIn PDF document text
    • http://bdsps.org/slbdavbatala/userfiles/file/vuregu.pdfIn PDF document text
    • http://sooam.com/files/fckeditor/file/13021618106149f41d1a2c4.pdfIn PDF document text
    • https://tttinox.com/upload/userfiles/files/37386796159.pdfIn PDF document text
    • http://builderall.info/userfiles/file/ruvavalumaborixinapok.pdfIn PDF document text
    • https://brtim.com/uploads/wysiwyg/files/5745412358.pdfIn PDF document text
    • http://yuc-fac.com/uploadfiles/20210919140908.pdfIn PDF document text
    • http://www.frank-diagn.hu/userfiles/files/40408165174.pdfIn PDF document text
    • https://habibitours.net/ckfinder/userfiles/files/fapolu.pdfIn PDF document text
    • https://asiantms.com/ckfinder/userfiles/files/11433846051.pdfIn PDF document text
    • http://vimar.ua/userfiles/files/foniguguvagijunazid.pdfIn PDF document text
    • https://arerp.kr/data/file///turuwomexatuvog.pdfIn PDF document text
    • http://primethailand.com/ckfinder/userfiles/files/digewusaji.pdfIn PDF document text
    • https://corcreation.twbiz.me/data/fckeditor/files/20210907_235129.pdfIn PDF document text
    • http://worshipedia.mobi/sites/default/files/file/25987780859.pdfIn PDF document text
    • http://daglichtfilters.nl/ckfinder/userfiles/files/sevolubeje.pdfIn PDF document text
    • http://mobilenmr.com/files/files/nitejixegabozubosiruxi.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135c1098b29c---kamasuzer.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_off0000bb38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBB38 10824 bytes
SHA-256: 2db6bafe52201929f354c040a23f652a0f1e236524f8ce85352f73c0504c1d6e
font_01_sfnt_off0000d3f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3F9 19456 bytes
SHA-256: 0b17fbf52c1b5b649a0248ce377ec9f5cf015f43d2026d813d587a6c62054a85
font_02_sfnt_off0001069b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1069B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1