Malicious PDF — malware analysis report

Static analysis result for SHA-256 25f77f04440097a2…

MALICIOUS

PDF

83.7 KB Created: 2021-09-16 20:46:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 7e26443c2503994e064daa9780167efc SHA-1: 6960c07bbbef589428e9e1b44155dea86b7542c5 SHA-256: 25f77f04440097a229720aea3464685ace793d2387310f1b021952ff3aa5830a
174 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file detected as malicious by ClamAV and an ML classifier. It contains embedded JavaScript and numerous external links, many of which point to disposable hosting and appear to be part of a link farm. The presence of embedded JavaScript suggests an attempt to execute code, likely to download a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9984

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://wastran.ru/uplcv?utm_term=wonder+woman+stream+online+free PDF link annotation
    • https://slide-bearing.com/d/files/17421358263.pdfIn PDF document text
    • http://kvrhousing.com/uploads/vixuxusetefinijirixeketo.pdfIn PDF document text
    • http://watdoenwevandaag.nl/upload/30758629558.pdfIn PDF document text
    • http://generale-bureautique.fr/gdb/files/file/88670055232.pdfIn PDF document text
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613535f25a615---kedudu.pdfIn PDF document text
    • http://dichvugiayphep.net/hinhanh_fckeditor/file/zopenuzonolasegiwipekeji.pdfIn PDF document text
    • https://afritransport.com/app/webroot/files/file/vanuniziridowolemabo.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/78691578f4b3f5ad76726e7eb0ca6412/52742642162.pdfIn PDF document text
    • http://tanabuauto.com/js/upload/files/suvubokoxofibateko.pdfIn PDF document text
    • http://arcdesantmarti.com/biocop/Images/images-editor/file/1103835734.pdfIn PDF document text
    • https://siriusdynamics.com/assets/uploads/files/bedijawumakuwono.pdfIn PDF document text
    • http://mistral-paints.cz/userfiles/files/xenotowimixajoxegoli.pdfIn PDF document text
    • http://gardatrans.com/content/Files/fusoxux.pdfIn PDF document text
    • http://hoanhaochemical.com/uploads/files/53873950759.pdfIn PDF document text
    • http://studiotecnicobonoli.com/userfiles/files/24078685674.pdfIn PDF document text
    • http://xn----7sbqwxdbhblh2h.xn--p1ai/data/file/3180540943.pdfIn PDF document text
    • https://digireg.nz/upload/kokevepenudogusabuwiso.pdfIn PDF document text
    • http://lex.tj/img/file/75326785149.pdfIn PDF document text
    • http://bippex.com/filespath/files/20210913163808.pdfIn PDF document text
    • https://alshamiltrading.com/alshamilfiles/file/vumurirewolaki.pdfIn PDF document text
    • https://internationallanguagenavigators.com/media/pixamisedosokogi.pdfIn PDF document text
    • https://signatureshreyas.in/userfiles/file/7931916162.pdfIn PDF document text
    • http://chochosanencino.com/uploads/files/jutilezufugupafozot.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_off0000de1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE1B 18984 bytes
SHA-256: 13ecdfa4a7be37f3c000de553f4fb92470da9de0d53d1f131e4f03b4415c38eb
font_01_sfnt_off00011099.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11099 10596 bytes
SHA-256: 00861b13a94f427eddc849eb3a4e6b01334ad1a94e72c8869da160622f8216d8
font_02_sfnt_off000128d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128D1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1