Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4551cb2b9c3b0eb…

MALICIOUS

PDF

87.7 KB Created: 2021-07-30 18:16:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: de7f5f5a3bfe85c9b1b60b5c966e029e SHA-1: 2c975a0375d07eb5efae158b64d93053be0ef6b5 SHA-256: c4551cb2b9c3b0eb2bec0ad3e9e64c6a65f561188db2c2c311f9b669d48738f8
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it contains embedded JavaScript and numerous external URIs pointing to compromised WordPress upload storage and other disposable hosting, suggesting it's part of a link farm designed to distribute malware. The presence of a 'download button' lure further supports a phishing or social engineering attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 8

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://wastran.ru/uplcv?utm_term=bytefence+anti-malware+pro+serial+key+free
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ec76cc54c1---bomixorixuwiduwepepof.pdf
    • http://osheamaloneynylaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/82109701598.pdf
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b9d62aa8f77---jamezurazixosewo.pdf
    • https://apartmani-mestrovic-krk.hr/files/voperez.pdf
    • https://archltginc.com/wp-content/plugins/super-forms/uploads/php/files/e140afb0e330a4a8811a052b3a54c7ef/sedilafiwowa.pdf
    • http://xn--b1afklwjc5g.xn--p1ai/ckfinder/userfiles/files/90349458684.pdf
    • https://humantouchtranslations.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/160aa62b9e4a0e---21638069580.pdf
    • https://vdbergelectro.nl/wp-content/plugins/super-forms/uploads/php/files/86512598d230e154e457aec48fc89a8a/duzeloba.pdf
    • https://rebates.forex/wp-content/plugins/super-forms/uploads/php/files/hlkcn01vth5p02m0u40ntumuv6/77659182980.pdf
    • https://imapcb.org/wp-content/plugins/super-forms/uploads/php/files/och41m3qvgsbuik9ifpmfrrhj4/bobubatenumefaj.pdf
    • http://orbitsecurity.qa/pro_mvp_tech/uploads/file/jezosomumunojizugazivavi.pdf
    • https://soyana.de/js/ckfinder/userfiles/files/lobobinozan.pdf
    • http://bagpack.com.np/wp-content/plugins/formcraft/file-upload/server/content/files/160afbe8ebac65---xatubevezaserularuruda.pdf
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16094940e859b2---72125409213.pdf
    • http://www.x454.com/wp-content/plugins/super-forms/uploads/php/files/1nq4sdsb585fi2tds00nc3b7f3/52855877056.pdf
    • http://scherzerpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tirotetofirifesisejeje.pdf
    • https://samngaimarble.com/html_upload/file/75792956944.pdf
    • https://sahyadrisevasanstha.in/userfiles/file/87552012655.pdf
    • https://investmentskillsgroup.com/images/userfiles/file/zinuvawubigixisojejexamop.pdf
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16093bde013f99---vezabatidegugaxoxusovet.pdf
    • http://divodizain.ru/ckfinder/userfiles/files/xikexobuponopate.pdf
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/16078444c65eb7---julaj.pdf
    • http://ewhamd.net/upFiles/ckeditor/files/97002382734.pdf
    • https://peilimineko.com/userfiles/file/64620853877.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_off0000f28a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF28A 16792 bytes
font_01_sfnt_off00010aa1.bin
717ca9783925cb8ea7c9cd3c4c0b9108bab9abbf097703a6ad9c1126070bb244
pdf-font-stream PDF embedded font (sfnt) at offset 0x10AA1 11020 bytes
font_02_sfnt_off00012466.bin
99a08955fa5c8d53c5e6947526884385f86c965c12d1affa3a4883eaaebe74aa
pdf-font-stream PDF embedded font (sfnt) at offset 0x12466 16896 bytes