Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b664413cd075ef4…

MALICIOUS

PDF

93.6 KB Created: 2021-07-04 13:53:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 088f0953500047817b07263129aa1b7f SHA-1: 418b43fd2f6bc1530831b414e505454a005814f3 SHA-256: 9b664413cd075ef44d1d80e7d145d45692211b365394501fc87e54a24923a443
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of embedded JavaScript, though not fully analyzed due to obfuscation, likely contributes to the malicious functionality by facilitating the redirection or payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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=content+and+pedagogy+for+the+mother+tongue
    • https://thietbivesinhanhhuy.com/asset/files/51521201783.pdf
    • https://monuments-msk.ru/wp-content/plugins/super-forms/uploads/php/files/4e5a2316d186fa6b69afc3ef0ca89a83/13682516410.pdf
    • http://totaleclipsenv.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5907a4cfe5---sirokexubimepedimiz.pdf
    • https://dadrarad.ro/userfiles/file/90682279508.pdf
    • https://faltprasten12.se/anvandarbilder/70/files/limugupizub.pdf
    • https://www.ergunaygoren.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072d56588af6---vamofifagu.pdf
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160779721c665e---bipaxixezorufidonojoko.pdf
    • https://machnhaduong.com/images/uploads/files/sodil.pdf
    • http://indemo.pl/Image/files/79668547790.pdf
    • https://medprobr.com.br/wp-content/plugins/super-forms/uploads/php/files/0ef55200f2fa201912046ab4290323e3/58046589593.pdf
    • https://sieuviet.net/webroot/img/files/jovijixuzaxe.pdf
    • http://aep-tc.com/cache/fck_files/file/85373397596.pdf
    • http://www.heksan.com.pl/file/63281898068.pdf
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/lo78hft4lo3o30ufrof16iu9ph/zodexinawimube.pdf
    • https://greenline.bg/userfiles/file/62106503816.pdf
    • http://thebellingerfamily.com/clients/0/05/05034faaa501c69409a7459485cba135/File/37081687244.pdf
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b303faa101c---89277728014.pdf
    • http://mountmedpharmacy.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1606f9170a60b4---texalivinimo.pdf
    • https://srp-galabau-rostock.de/wp-content/plugins/super-forms/uploads/php/files/rq04q7h78kv28o2n2825ml9qq8/39564104341.pdf
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607bf7b36ec25---vonubejawinofaguzupebexe.pdf
    • https://ipcare.nl/wp-content/plugins/super-forms/uploads/php/files/7ars9uuhlmic8rnsvqbrpcvviv/25703939118.pdf
    • http://casaatlantida.com/userfiles/file///20980067987.pdf
    • https://pilotcenter.gr/wp-content/plugins/super-forms/uploads/php/files/d4d203167c85f8cee30452dd8a5cf818/62009731711.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_off0000ec9f.bin
dc1904e982edee671b621f71cde975756e2b3240ae4703b269b23e6342020822
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC9F 10884 bytes
font_01_sfnt_off00010576.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10576 16792 bytes
font_02_sfnt_off00011d88.bin
65855327aee2bb362d333322ab6b5b4b9119fbb881cbac19a8183d0953880f6e
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D88 31612 bytes