Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca929a77847e273c…

MALICIOUS

PDF

82.1 KB Created: 2021-07-06 15:47:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dfc80290fb8a2e2f534a9be5cae8b411 SHA-1: b98d6f62097f2308cc9efa6244f3391251f4e9ba SHA-256: ca929a77847e273c81802c0d301028b09ac18440bab6119c6df688f208360d45
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to numerous other PDF files hosted on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The structure suggests an attempt to obscure the final destination by using multiple layers of redirects.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • 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.
  • 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://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba674d51c1c---3398271757.pdf
    • http://sevinctekstil.com/resimler/files/97641062232.pdf
    • http://agro-pasz.pl/ckfinder/userfiles/files/19112468589.pdf
    • http://treeoflifetolfu.com/clients/0/07/07f122ebb3396bb3f917f2e62af81596/File/naxukubibogejafebosutawa.pdf
    • http://associacaoguainumbi.org.br/wp/wp-content/plugins/formcraft/file-upload/server/content/files/16094b074da251---rokawutibadexom.pdf
    • http://www.canadavisaservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085112c94a45---lubin.pdf
    • https://www.hausbootgeiseltalsee.de/wp-content/plugins/super-forms/uploads/php/files/7pv8anqrjdqm99jbu0ndk77nst/34082061341.pdf
    • https://fulzugaskozpont.hu/files/51543659322.pdf
    • http://pobierzplik.pl/uploads/files/21804014087.pdf
    • https://poolpoint.be/uploads/file/62178341076.pdf
    • http://tourbusan.net/FileData/ckfinder/files/20210614_F6ED229C6A7157C6.pdf
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160aa0a69c089f---xulugow.pdf
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/21ff60fbede6c4674b9a35473899d236/majaxor.pdf
    • http://jnnycc.org/userfiles/file/guwekowuxikemupow.pdf
    • https://www.tunnel.de/files/uploaded/file/lupun.pdf
    • https://morethancleaningservices.com/wp-content/plugins/super-forms/uploads/php/files/e0be84a9136957e790885879140ba2b0/vosonedot.pdf
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077e365c9bac---30779491730.pdf
    • http://matchonusa.com/uploads/files/15684528483.pdf
    • http://sciencevier.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cf13cd5239a---96602188710.pdf
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/80998675910386b77052dc6bfaece99e/10404384583.pdf
    • http://humanitool.ru/userfiles/file/6469243077.pdf
    • http://syuncyoku.jp/upload/file/guwenuvudoxabapelabubun.pdf
    • http://bukharageorgia.com/sites/default/files/file/17788336120.pdf
    • https://shared401k.com/wp-content/plugins/super-forms/uploads/php/files/f1cae231c7a3d0cd49ae531fd6a25033/77668549716.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=electron+dot+structure+for+c
    • 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_off0000e014.bin
0cc3a9d3fccf648709da66ba52a6a3bac2ccb1201cd897e774241772484c5532
pdf-font-stream PDF embedded font (sfnt) at offset 0xE014 10300 bytes
font_01_sfnt_off0000f766.bin
23841feb8171d0896e8a6cc8454339e4f79eb2c14fc50a8d2fe0de9ddc86ab49
pdf-font-stream PDF embedded font (sfnt) at offset 0xF766 16720 bytes
font_02_sfnt_off00012357.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12357 16792 bytes