Malicious PDF — malware analysis report

Static analysis result for SHA-256 9a308f403087e112…

MALICIOUS

PDF

88.2 KB Created: 2021-08-17 05:56:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ce86cf76317e3ff41b65dce9b33d3e99 SHA-1: 895d6e99fabbb7af77748b61bc09d757cd4231ea SHA-256: 9a308f403087e11247462f47041f05371c9280412fed72301c736cf94a8f9c7b
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous external URLs, several of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The document body is heavily obfuscated, preventing a clear understanding of its specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9912

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://jarosi.hu/files/file/52338855897.pdf
    • https://ivanamihic.com//files/16094770575.pdf
    • http://hoangnamjsc.com/upload/files/88733700695.pdf
    • https://actaviaserica.org/board/file/files/zuzuwafabudimojulofi.pdf
    • https://www.lightingsolutionsinc.net/wp-content/plugins/super-forms/uploads/php/files/5ba9df81c387c6c1a9d97f7c20672135/5449748083.pdf
    • http://asbufestival.com/uploads/FCK_files/file/ratavomabovo.pdf
    • http://greenhousehotel.vn/uploads/image/files/lazagebuneg.pdf
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608f0d026a36a---dalipusitenabojunu.pdf
    • http://iccj.jp/images/uploads/fckeditor/file/sajowaxanobuzufapo.pdf
    • http://www.specemc.ru/upload/files/90405194552.pdf
    • https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f8678dedc6---64539172738.pdf
    • https://mvpartners.be/images/uploadedimages/file/biladawututirize.pdf
    • http://www.yoko-ono.be/images/userfiles/file/95300723923.pdf
    • http://koreadramatour.com/FileData/ckfinder/files/20210627_5ACA42DA8A751676.pdf
    • http://thm-holding.ru/wp-content/plugins/super-forms/uploads/php/files/6d2d980b4ce6c50e4511ed9a2250d60f/gijopezoxipumuxide.pdf
    • http://thietbixanh.net/uploads/files/38385429114.pdf
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/160ac1713549eb---wobijedol.pdf
    • https://koncnc.com/genelresimler/file/walugazemon.pdf
    • http://domusanna.it/userfiles/files/feropokujegobovowufakal.pdf
    • https://www.charityweiss.de/wp-content/plugins/formcraft/file-upload/server/content/files/160949b045dc0d---jogebegizibomomapomunugok.pdf
    • https://na-nule.ru/wp-content/plugins/super-forms/uploads/php/files/3qa840es2cjfsa5pgfto1mpnt6/fonejuve.pdf
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160988c873fc4f---37981160339.pdf
    • https://embassyinvietnam.com/webroot/img/files/lazukiguverigosoku.pdf
    • http://daiichigroup.net/uploads/news_file/70910115732.pdf
    • http://ar-intl.net/wp-content/plugins/super-forms/uploads/php/files/jhpu3r69ap8bf54klqnao9kqn2/tovijikonifugulisosodalak.pdf
    • http://thunderstar.cn/userfiles/file/20210701145012265510800.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=snapple+flavors+discontinued
    • 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_off0000f471.bin
a30313fb808061faf5d6b01eae0387827ed9bf71d6258d45b87bcb8cebb52167
pdf-font-stream PDF embedded font (sfnt) at offset 0xF471 16812 bytes
font_01_sfnt_off00012055.bin
bbf5ceabdfbe54bd86f933a092705f7561fbb48882ef9bae24b65a60315bd01f
pdf-font-stream PDF embedded font (sfnt) at offset 0x12055 10856 bytes
font_02_sfnt_off0001398c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1398C 16792 bytes