Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9dd123601723ca3…

MALICIOUS

PDF

82.2 KB Created: 2021-09-11 19:38:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: e079ac3fcd16631b5d7c37f18a43dad4 SHA-1: 2b56d4f529077de2be645cc3433812ef5749c061 SHA-256: b9dd123601723ca3f4cbca50ace1cb423afd803ef244d0249f9f5cf4c8c6104f
164 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, directing users to compromised WordPress upload storage and other disposable hosting sites, likely to facilitate malware distribution. The presence of a 'download button' lure further supports a phishing or social engineering attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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 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.
  • 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://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/161338d9f96d46---16499992080.pdf In PDF document text
    • https://biserica-izvorul-tamaduirii.ro/files/dowenirob.pdfIn PDF document text
    • http://kimhoatra.vn/upload/fckimagesfile/nalaxa.pdfIn PDF document text
    • http://goodlife88.com/uploads/files/metubujenenarikid.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130da9dc5dae---61522002384.pdfIn PDF document text
    • http://louisefarmersmith.com/admin/ckeditor/ckfinder/userfiles/files/dalaxurixamumegibunarapez.pdfIn PDF document text
    • http://fs-select.com/images/blog/file/rabopunogukizijomevabif.pdfIn PDF document text
    • https://soi.icami.mx/ckfinder/userfiles/files/kunalege.pdfIn PDF document text
    • https://adtw1.elfjane.com/ckfinder/userfiles/files/togugirabuxupemerufuv.pdfIn PDF document text
    • https://www.bosingels.nl/ckfinder/userfiles/files/fakivunujejiwame.pdfIn PDF document text
    • http://ebus.cn/up_file/file/zagisofevamufozawi.pdfIn PDF document text
    • http://www.yevres.fr/ckfinder/userfiles/files/werovevadirapex.pdfIn PDF document text
    • https://crownprolaw.com/userfiles/Proj_Name/files/pibigafazofiraxigufegired.pdfIn PDF document text
    • http://www.vlaamspatientenplatform.be/_plugin/ckfinder/userfiles/files/loraxaf.pdfIn PDF document text
    • http://trustycctv.com/ckfinder/userfiles/files/68121527195.pdfIn PDF document text
    • http://henzefashion.com/userfiles/file/pebevakizokeduvivoke.pdfIn PDF document text
    • https://pre-www.bridge-college.com/uploaded/ckeditor/files/4500043084.pdfIn PDF document text
    • http://swiftnb.com/ckfinder/userfiles/files/wapanisifa.pdfIn PDF document text
    • http://studiomarazzi.eu/userfiles/files/97903485989.pdfIn PDF document text
    • https://www.drmarlenebothma.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613688f31cbd9---zenemizedokegulunifadon.pdfIn PDF document text
    • http://cascinamana.it/userfiles/file/rabegoripimibelimig.pdfIn PDF document text
    • https://guruamardaspublicschool.com/userfiles/files/84464518808.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/161381b2e98da9---67888864411.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/16137c28209c8d---vupam.pdfIn PDF document text
    • http://sumbulefendiegitimvakfi.com/resimler/files/tavupa.pdfIn PDF document text
    • https://kamber.dk/wp-content/plugins/super-forms/uploads/php/files/c193087853b5ff69a63ebb502df38d82/zogipinabim.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=download+game+minion+rush+mod+apk+offlinePDF 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_off0000dbb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBB6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f3cd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3CD 11128 bytes
SHA-256: fe5c52ba932cbe89c5c66ecb856462ed19ea3a7b0bd09bfaed23bd3b7b9ee081
font_02_sfnt_off00010d5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D5E 17780 bytes
SHA-256: d78ab85cdc3acc6e5e9fb15002e2e82d5ceff2b965dab4b73ae95e1f99372a6e