Malicious PDF — malware analysis report

Static analysis result for SHA-256 23a33accd8feb3d7…

MALICIOUS

PDF

87.4 KB Created: 2021-07-01 20:20:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4f14343c1f2806c8da26dd1018219700 SHA-1: f74f136e21b3c92ef15ebc857b9e66bc657aad39 SHA-256: 23a33accd8feb3d79b601a74867580884114cc9b6e18da4553ad83286edf66c4
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains embedded JavaScript and a link farm pointing to multiple compromised WordPress sites, suggesting it's designed to redirect users to malicious content. The primary attack pattern involves using these links to deliver a secondary payload or conduct phishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/832611c80d997ec1714eeec2dd9b63eb/lumorojedogopevab.pdf
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a63b80d86e1---34061362538.pdf
    • https://robotics-institute.com/wp-content/plugins/super-forms/uploads/php/files/qhnpoo3bgsrhgrk7d6iuf0m2mp/pamowubazapizeratepuvopa.pdf
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f223ac4636---gezaret.pdf
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/16071602c995cd---57534548700.pdf
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608d0c89e99b7---kanojajo.pdf
    • http://korvet-sp.ru/userfiles/file/gurozoxilugenu.pdf
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/4c76297570ba485d0f3c375a80673920/misogifen.pdf
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/a46461c279c984d455baaab0af608c11/monugasofepak.pdf
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1846f20101---55456244189.pdf
    • https://akdenizokullari.k12.tr/wp-content/plugins/super-forms/uploads/php/files/1p1t8n5thmcmc3fbnf1s8r5ptf/waxozafiwepoteju.pdf
    • https://ceadersvalet.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b46654ba4b5---doxiratelu.pdf
    • http://lhsclassof68.com/clients/73441/File/zoromagovaz.pdf
    • https://landbondcorten.com/attachment/file/aa092299a7896e9b90311c9fc369c0bb.pdf
    • https://mrmusicfoundation.org/wp-content/plugins/super-forms/uploads/php/files/rmetp80rkkg041f7nf64i2bl68/vudiwuguwuxek.pdf
    • https://accesoriosalmayor.com/images/userfiles/file/90442674869.pdf
    • http://www.herbertvanderbrugghen.nl/draft/sofefejudaviwamezugivuxa.pdf
    • https://soyana.de/js/ckfinder/userfiles/files/vugadokuzapawewip.pdf
    • https://weddingitaly.jp/images/file/99229644964.pdf
    • https://syteq-pro.com/userfiles/file/19316997740.pdf
    • http://opalbiosciences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab918fa02ca---begoduzixonirirezabinub.pdf
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160731ff445d43---bofugubewud.pdf
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/a5g23niijkf0k0pr3lcc5uj9jr/97009115162.pdf
    • http://teormech.ru/teormech/usrimg/file/tewekudamu.pdf
    • http://fcv-bo.org/data/fcv-bo/userfiles/file/1516652200.pdf
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/0ea612d66b890bd21d021278f0a90538/99780697696.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=still+waters+run+deep+meaning+in+malayalam
    • 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_off0000ec9d.bin
710ffb53b6cad40da0f762c9a28b2945cadd2d8979c2a1fbd1dae10ee104491d
pdf-font-stream PDF embedded font (sfnt) at offset 0xEC9D 10992 bytes
font_01_sfnt_off000105e7.bin
42a864de8c6bcc1774420b1e54a34c12584566f8bdd5360f7d67d1386a97289c
pdf-font-stream PDF embedded font (sfnt) at offset 0x105E7 18248 bytes
font_02_sfnt_off00013558.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13558 16792 bytes