Malicious PDF — malware analysis report

Static analysis result for SHA-256 cb65d54c38a349c8…

MALICIOUS

PDF

81.6 KB Created: 2021-09-13 12:09:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 22995faa0564e995aed2e1dffece1fc0 SHA-1: 88eec05857679ab2f2f38cb41f7784eb85ce6d83 SHA-256: cb65d54c38a349c8425343b9fa8b1566c477a8b56f7cc3acd32cdcecd76ce9b1
134 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm with a deceptive download button, aiming to trick users into downloading further malicious content. While no scripts were directly extracted, the nature of the PDF and its embedded links suggest an attempt to exploit vulnerabilities or deliver a payload, likely via JavaScript execution within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://nwatchonline.info/userfiles/file/gobemezofovalevatinebikak.pdf In PDF document text
    • https://uat-tunisia.com/userfiles/file/61732530143.pdfIn PDF document text
    • https://pollackmihalyiskola.hu/ckfinder/userfiles/files/96694476799.pdfIn PDF document text
    • http://daphongthuyhueminh.com/uploads/image/files/bodupifejineleredajumax.pdfIn PDF document text
    • http://asbu.net/uploads/FCK_files/file/64959900854.pdfIn PDF document text
    • http://i-harmonics.com/upload/files/pedipisomu.pdfIn PDF document text
    • http://hum-lucknow.org/test/fckeditor/file/55241499433.pdfIn PDF document text
    • http://getrade.net/uploadfiles/file/zuxotari.pdfIn PDF document text
    • https://cissud.eu/uploads/ck_editor/files/95551794698.pdfIn PDF document text
    • http://www.abcklima.hu/data/editorfile/xopilusobekopuduxijogu.pdfIn PDF document text
    • http://rayocazar.com/images/elfinder-1.1/files/file/88224834022.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613763deec59e---mizejexabumewonudalin.pdfIn PDF document text
    • https://yasacompany.com/upload/files/fozexarojoruz.pdfIn PDF document text
    • https://markmont.eu/editor_uploads/system/files/koredujukipanikut.pdfIn PDF document text
    • http://jucal.es/images/file/wakofozigunoladizet.pdfIn PDF document text
    • http://www.ruben.pl/ckfinder/userfiles/files/26406097588.pdfIn PDF document text
    • http://energyexcess.com/userfiles/file/jiwugapifajivenef.pdfIn PDF document text
    • https://brihat-group.com/assets/userfiles/files/fekubowimetorogedomul.pdfIn PDF document text
    • http://hosteleriayvending.com/ckfinder/userfiles/files/dodikemotep.pdfIn PDF document text
    • http://stonebreaker.at/lupalirum.pdfIn PDF document text
    • https://tavfelugyelet.megujuloenergiapark.hu/admin/ckfinder/userfiles/files/pebikevixazewuma.pdfIn PDF document text
    • http://healingtown.org/userData/board/file/44344471302.pdfIn PDF document text
    • http://thoitranglani.com/upload/files/2587513856.pdfIn PDF document text
    • http://awarelaxcentrum.cz/user_files/file/tuwutorazewigiwixujavamil.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=8+ball+cheto+hackPDF 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_off0000d930.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD930 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f147.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF147 10208 bytes
SHA-256: 0a968a3d8415808507a9a3dee200934081cc98758bd9fc61dd852373fba2e37c
font_02_sfnt_off00010854.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10854 18920 bytes
SHA-256: fbdadd7d83a4649833a748c9ce645e3889f1270990e0015ce35bf9f964f62f19