Malicious PDF — malware analysis report

Static analysis result for SHA-256 23cbe16f5a382934…

MALICIOUS

PDF

87.0 KB Created: 2021-07-30 19:57:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: e1b8d4fa6c3b77eb043c569b10fabe4d SHA-1: 1486c88f2a6c7cd227cddfe5b4c91af4920f4937 SHA-256: 23cbe16f5a382934213fd656b649cf92617a46edd333919ecbf87fd612da859d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, many pointing to compromised websites and disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further reinforces this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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 http://dailyxedayhang.com/userfiles/files/famunatujunapaze.pdf In PDF document text
    • http://vilaportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c305f86827e---xulimexijuruxivugituvewex.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/fefe7410566c67d4dccd93a5e6215543/fogakipotudibatunavokev.pdfIn PDF document text
    • http://www.ortodonciaelisafarache.com/ckfinder/userfiles/files/28607386876.pdfIn PDF document text
    • https://www.elementstraining.co.uk/wp-content/plugins/super-forms/uploads/php/files/va0fmui5a0hcrhg83rsnujp9j6/zobenov.pdfIn PDF document text
    • http://aiswaryamatrimonials.com/fck_uploads/file/56631434808.pdfIn PDF document text
    • http://sazjah.com/wp-content/plugins/formcraft/file-upload/server/content/files/160901ed66936a---ruxijegerivo.pdfIn PDF document text
    • http://gpkoaee.ru/ckfinder/userfiles/files/koviluvivuf.pdfIn PDF document text
    • http://omgmediatank.com/userfiles/files/34264836688.pdfIn PDF document text
    • http://abc-tel.ru/data/File/19432089653.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ef377bb4c2---31065449666.pdfIn PDF document text
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f7cb523573e---tizaxulig.pdfIn PDF document text
    • https://buddingheights.org/wp-content/plugins/formcraft/file-upload/server/content/files/160cf880ca732d---71526575472.pdfIn PDF document text
    • http://fitviewer.info/files/file/67133377073.pdfIn PDF document text
    • http://xn--e1aazeoc7d.xn--p1ai/images/shared/file/kuronezif.pdfIn PDF document text
    • http://howsonfamilyreunion.com/clients/5/57/57b8fe7d350e782a16e6afc8bdcd6467/File/89975063079.pdfIn PDF document text
    • http://lirealestatelitigator.com/wp-content/plugins/super-forms/uploads/php/files/6eb8d0edd1000e98b864335fb515dbb3/tubetosaro.pdfIn PDF document text
    • http://whuntex.ru/userfiles/file/34893516224.pdfIn PDF document text
    • https://btegypt.com/file/50205448925.pdfIn PDF document text
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606cf35b2b9d3---jawuragirejofipuguwuki.pdfIn PDF document text
    • http://kinel-hunter.ru/upfiles/file/84792503464.pdfIn PDF document text
    • http://caudafotografia.com/userfiles/files/93274915661.pdfIn PDF document text
    • https://total-sport.pl/img/upload/files/wupotavimejaxu.pdfIn PDF document text
    • http://bakoca.hu/files/file/didujunevafadojebijab.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=fce+reading+comprehension+pdfPDF link annotation
    • 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_off0000eea5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEA5 17344 bytes
SHA-256: 9e868c04391cacfbc26d458fcd98f4706cc33faf1f2ad75e9c2ed84d6afb1a9d
font_01_sfnt_off00011c12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C12 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013429.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13429 10900 bytes
SHA-256: 4d168c40f39c46938078dd26529ef42682d53f77b2899079ab1e1b98fa8e693f