Malicious PDF — malware analysis report

Static analysis result for SHA-256 aac0524f1d9d38a9…

MALICIOUS

PDF

70.8 KB Created: 2021-10-04 00:57:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 7a84c25b0caf9d35716e2cf2d74dac48 SHA-1: 2c1ff9192e23eedee25df4c46600fb01a0024792 SHA-256: aac0524f1d9d38a91a2a203c714616cd370154cef89c2e6296fc613cb7a17bfa
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains embedded JavaScript and a large number of external URIs, many of which are hosted on disposable domains. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The embedded JavaScript is a common technique for initiating malicious actions within PDF documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9909

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://nomylo.ru/uplcv?utm_term=nested+loop+syntax PDF link annotation
    • http://bhk-aindling.de/userfiles/files/vofibizoduxegosurajeve.pdfIn PDF document text
    • https://yarpaket.ru/userfiles/file/modemopisowujol.pdfIn PDF document text
    • http://porpora.biz/imagenes/imagenes_contenidos///xibafutujunibexowujirase.pdfIn PDF document text
    • https://tanthueviet.vn/img_data/files/gesel.pdfIn PDF document text
    • https://royal-art.pl/uploads/userfiles/files/kunipifozid.pdfIn PDF document text
    • https://ptkas.com/kingkong/userfiles/files/98338317956.pdfIn PDF document text
    • http://ichieh.tw/uploads/files/202109301344416007.pdfIn PDF document text
    • http://kyokushin96.ru/admin/ckfinder/userfiles/files/pixinesopafafonodetiviro.pdfIn PDF document text
    • https://markyatirim.com/resimler/files/kamod.pdfIn PDF document text
    • http://eskuvotoszkanaban.hu/editor_up/javiven.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/161582afd1be34---xilinegatipitujoxig.pdfIn PDF document text
    • http://cathyknightwaite.com/ckfinder/userfiles/files/15458485263.pdfIn PDF document text
    • https://12shio3.com/contents/files/64173979783.pdfIn PDF document text
    • http://amandatravel.com/userfiles/file/76291995605.pdfIn PDF document text
    • http://gzafjc.com/uploadfile/files/55822919493.pdfIn PDF document text
    • https://getracemirates.com/userfiles/files/91175965399.pdfIn PDF document text
    • https://matfplayer.com/calisma2/files/uploads/80816951216.pdfIn PDF document text
    • https://52fantasies.com/home/holly/public_html/ckfinder/userfiles/files/63542732039.pdfIn PDF document text
    • https://stmpallet.com/ckfinder/userfiles/files/denikisir.pdfIn PDF document text
    • https://ckmusicdesign.nl/userfiles/file/26187522546.pdfIn PDF document text
    • http://tfh-filter.hu/_user/file/62525974729.pdfIn PDF document text
    • http://didongsinhvien.com/upload/files/29857773557.pdfIn PDF document text
    • http://vatlieulamnha.com/media/ftp/file/muzabudetusavalolekebi.pdfIn PDF document text
    • http://aviapartner.biz/js/ckfinder/userfiles/files/50541340134.pdfIn PDF document text
    • https://506hlapeta.com/files/file/dudenidagulezudawuz.pdfIn PDF document text
    • https://vsetinrally.cz/userfiles/file/nurakopaguxuxitusovamelak.pdfIn PDF document text
    • https://seeyounow.net/userfiles/file/zulumibibimodamiraduvir.pdfIn PDF document text
    • https://movimientofamiliadejesus.com/images/uploaded/file/44478353547.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_off0000b742.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB742 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cf54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF54 15020 bytes
SHA-256: 908003cd536b2b1d4190953df50816fb3770e7eecfc786aabec30346e4fb7102
font_02_sfnt_off0000f569.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF569 10388 bytes
SHA-256: 77e1da426294216319793479c11b4f7469bdcccdbdb2800264112654cc3870d2