Malicious PDF — malware analysis report

Static analysis result for SHA-256 2660afce3b493414…

MALICIOUS

PDF

91.4 KB Created: 2021-09-12 20:10:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: c0e09c70bf690c9b62d17df40cf5a3a2 SHA-1: 1fdb2f76f23a5eda4e3436d16d28607c64643fb1 SHA-256: 2660afce3b493414148f788468e2f304a2416815842ee3dcba43042f5928f64b
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. The PDF contains a large number of embedded URLs pointing to disposable domains, a common tactic for link farms used in phishing campaigns. The `PDF_SEO_DISPOSABLE_LINK_FARM` heuristic specifically flags this behavior, suggesting the PDF's primary purpose is to redirect users to malicious content or further stages of an attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://doanhnghiepvietnam.niengiamdoanhnghiep.vn/img_duhoc/files/tiguredu.pdf In PDF document text
    • http://www.oiseaubleu-promo.fr/userfiles/file/verasasifawoxirevevekefe.pdfIn PDF document text
    • https://postelezmasivu-zlin.cz/ckfinder/userfiles/files/57510532089.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d60411ad53---kariwubivanul.pdfIn PDF document text
    • http://westfallassociates.com/documents/file/65634363183.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/ed766783fcc08d7ca61e97f3bb7f25c9/9978500995.pdfIn PDF document text
    • http://tehpromyar.ru/media/file/70164403644.pdfIn PDF document text
    • http://ski-experience-japan.com/images/blog/file/28297767944.pdfIn PDF document text
    • https://autoteam.in/ckfinder/userfiles/files/37446340206.pdfIn PDF document text
    • http://murito.fr/ckfinder/userfiles/files/18182409069.pdfIn PDF document text
    • http://wsp.pl/userfiles/file/53917896547.pdfIn PDF document text
    • http://tw-jia.com/uploads/files/202109011708507215.pdfIn PDF document text
    • http://kdekdyjak.cz/data/5522368233.pdfIn PDF document text
    • http://ogledalata.bg/uploads/pages/files/situk.pdfIn PDF document text
    • https://www.cylinder96.ru/admin/ckfinder/userfiles/files/minokiguviladixari.pdfIn PDF document text
    • http://vwtint.com/userData/board/file/71343938419.pdfIn PDF document text
    • http://beiwendq.com/data/attachment/file/87348772671.pdfIn PDF document text
    • http://blbr365.com/userfiles/file/1630498986.pdfIn PDF document text
    • http://pro-group.ru/userfiles/file/fofomupikexedotijido.pdfIn PDF document text
    • http://houstontca.org/Content/uploads/files/takabepokalebeletofimova.pdfIn PDF document text
    • http://xingyeknitting.com/userfiles/files/domojalidizofaporuvetel.pdfIn PDF document text
    • http://www.atsamuihaus.com/image/upload/File/kepom.pdfIn PDF document text
    • https://osikovo.eu/webroot/img/content/files/50454964573.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=basket+ball+ioPDF 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_off000104b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104B9 10184 bytes
SHA-256: 938ef24d2e3f2806f36f31d40a84142581722bd58c86c8f55b79b9555c301197
font_01_sfnt_off00011bb8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BB8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000133ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x133CA 17280 bytes
SHA-256: 89e7c49969a93e215adf9cb05fdf4fe18cde7a68730df169fd1419d0e78dcb66