Malicious PDF — malware analysis report

Static analysis result for SHA-256 ae12626ee0094d82…

MALICIOUS

PDF

82.9 KB Created: 2021-09-21 15:23:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 7882e04d816c463889b836018662283f SHA-1: 682c838c604ccf49c09bae4ddc125c0c4b27481f SHA-256: ae12626ee0094d8284d3f506c36e5ae5f98a9c2beda1e72ff02cd109c1c27704
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm, suggesting a phishing or malware distribution campaign. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a deliberate attempt to obscure the true destination through redirects and a large number of distinct hosts. While no scripts were explicitly extracted, the presence of external URIs and the overall structure strongly suggest the PDF's purpose is to redirect the user to malicious content.

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://krisoc.ru/uplcv?utm_term=football+best+game+for+android PDF link annotation
    • http://stroi-sistema.ru/img/3936654713.pdfIn PDF document text
    • http://dierenwinkelindex.nl/images/uploads/12700852832.pdfIn PDF document text
    • https://spheresignal.com/app/webroot/userfiles/files/wudekali.pdfIn PDF document text
    • https://powermailer.in/userfiles/file/vatenixazesutawugazika.pdfIn PDF document text
    • http://www.leposeur.fr/site/upload/ckfinder/files/19249636919.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161341537340b5---90335253938.pdfIn PDF document text
    • https://costabravas.com/uploads/localidades/files/dafabamixem.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/161378f7bc7128---56546905815.pdfIn PDF document text
    • http://myapartment.de/web/editor/files/zugokamerutikix.pdfIn PDF document text
    • http://dongphat.net/upload/files/65460946644.pdfIn PDF document text
    • https://jcmimoveis.com/userfiles/file/4022338326.pdfIn PDF document text
    • http://ap116.ru/userfiles/file/38685071858.pdfIn PDF document text
    • https://parkettworld.com/upload/files/48621049908.pdfIn PDF document text
    • http://linklandhotels.com/upfile/editor/files/nukejasinivopunonejexufe.pdfIn PDF document text
    • http://xn--oy2b9bv81anouola.com/upload/file/202109201100344653.pdfIn PDF document text
    • https://mkontroll.hu/File/79007190200.pdfIn PDF document text
    • http://gainliving.com/upload/editor/file/84455226323.pdfIn PDF document text
    • http://ocean-ex.com/images/blog/file/62332859104.pdfIn PDF document text
    • https://www.eecpowerindia.com/codelibrary/ckeditor/ckfinder/userfiles/files/45002653437.pdfIn PDF document text
    • https://mujeresenmovimientoplus.com/userfiles/file/37372265464.pdfIn PDF document text
    • http://eyela.kr/uploadfile/fckeditor/file/13036922941.pdfIn PDF document text
    • http://zit-tech.com/userfiles/files/vafonamalib.pdfIn PDF document text
    • http://siamsnail.com/media/userfiles/files/xirogozinugig.pdfIn PDF document text
    • https://uroci-kursove.com/userfiles/file/81346565442.pdfIn PDF document text
    • http://ericshartman.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/48855508917.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_off0000e257.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE257 10812 bytes
SHA-256: 9c88955424bfbbc09ebb1ba4ccf3a94957f1a8bc94e09afbb93706fc5623452f
font_01_sfnt_off0000fb08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB08 16556 bytes
SHA-256: cc223f618d1a371ee548a148c33c75a313203587c077846d606bf06107142ce5
font_02_sfnt_off00012607.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12607 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1