Malicious PDF — malware analysis report

Static analysis result for SHA-256 b90ed0df52cd4ef7…

MALICIOUS

PDF

102.0 KB Created: 2021-09-08 18:37:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 86e6ff281044c15ff32fcdf1f55362f4 SHA-1: b254c6ff8e41a86a5625ee03105ce09da9dbb0e4 SHA-256: b90ed0df52cd4ef79ddaff10684f3bb13d1def7d632864a150578b8d5f3674fd
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that point to various websites, many of which appear to be compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The document body is heavily obfuscated and unreadable, but the presence of a link farm suggests an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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 https://laborke.ru/uplcv?utm_term=termodinamica+pdf+dispense
    • http://driver-jazda.pl/upload/file/43406745587.pdf
    • http://trendstyleimage.com/uploads/ckfinder/userfiles/files/21032229807.pdf
    • https://pass-eco-energies.com/ckfinder/userfiles/files/17864384499.pdf
    • https://tucarrorentacar.co/ckfinder/userfiles/files/nemotepava.pdf
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/1613357759a3bd---49404178866.pdf
    • http://kangshi-you.com/uploads/files/202109012302311694.pdf
    • http://www.taimaobi.com/admin/ckfinder/userfiles/files/fixifaridunapuk.pdf
    • https://led7.ru/file/gefopunusu.pdf
    • http://vijyaiprismcrm.com/userfiles/files/93216381317.pdf
    • http://omgmediatank.com/userfiles/files/79878174359.pdf
    • https://sushixusa.com/userfiles/files/fawibifuwawikiduk.pdf
    • https://pepsima.biz/files/file/18800596499.pdf
    • http://ilovegabal.net/fckeditor/_upload/file/91845274556.pdf
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613340d49fe73---75566619958.pdf
    • http://shuimotongyuan.com/userfiles/file/87177430903.pdf
    • http://kino-profi.com/wp-content/plugins/super-forms/uploads/php/files/fef387875702b5b3fe23dc771d995d1c/nobemux.pdf
    • http://www.trisad.kz/ckfinder/userfiles/files/makutepaxegakosul.pdf
    • http://polaryachtmanufactory.com/res/wysiwyg/file/vusejupiduzemuzo.pdf
    • http://iowatriallawyer.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/rulovomisu.pdf
    • http://tomaszfilipczak.pl/userfiles/file/vogowutuwudajitonedaw.pdf
    • http://jungam21.com/upfiles/file/1630742369.pdf
    • https://bokaichenyu.com/upload/files/33794679304.pdf
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134db4ac37d1---39242782444.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001228a.bin
f596a38f9a465f8c8c3a79bc6711cafcd92efb92ef4ec9ca5dc57f1dd15c0319
pdf-font-stream PDF embedded font (sfnt) at offset 0x1228A 21104 bytes
font_01_sfnt_off00015a29.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x15A29 16792 bytes
font_02_sfnt_off00017240.bin
788bca5f583bbec2e725d973911ff196a42e1a843fbee4cf10c798debb92b693
pdf-font-stream PDF embedded font (sfnt) at offset 0x17240 10600 bytes