Malicious PDF — malware analysis report

Static analysis result for SHA-256 d953dd7556a2c33b…

MALICIOUS

PDF

99.8 KB Created: 2021-09-05 09:50:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: a44964a6a3fab99f600c02c49b3cac67 SHA-1: a0c33310faa9cdd30ffa559b477520b1369b7676 SHA-256: d953dd7556a2c33b34af5f8ee03241250814214d955ad44b59e9209d0339db6a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, which is a common technique for executing malicious code. It also features a link farm pointing to multiple distinct hosts, many of which appear to be compromised WordPress sites, suggesting an attempt to redirect users to malicious content or download additional payloads. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9922

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://camile.vn/wp-content/plugins/super-forms/uploads/php/files/ghmi64p385et17olhcppmejoo4/zinagorajenosidor.pdf In PDF document text
    • https://zweiund40.com/wp-content/plugins/super-forms/uploads/php/files/f2fslovshpc8igcqnc3qukk79h/rebebe.pdfIn PDF document text
    • http://elandtour.com/FileData/ckfinder/files/20210807_E818CC6FB9528E0C.pdfIn PDF document text
    • http://www.tiande-global.com/ckfinder/userfiles/files/towut.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160fd9f240b157---vokulos.pdfIn PDF document text
    • http://toyotarentcar.net/FileData/ckfinder/files/20210630_8BBE6810209128C0.pdfIn PDF document text
    • https://sirikulsteel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab1a3c65a8f---sevoruwaja.pdfIn PDF document text
    • https://areshin.ru/wp-content/plugins/super-forms/uploads/php/files/b651da48dc61620535b46214f03862a8/zeteluvubutidiwomuruso.pdfIn PDF document text
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160805f411b86e---nefuvovonibunanodoloburo.pdfIn PDF document text
    • http://minuspk.ru/minuspk.ru/userfiles/file/guxomisumezib.pdfIn PDF document text
    • https://superpart.com/files/13200377794.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/4c251a7e08a8f33ec064ea73d3110c1b/mevuganexuxusum.pdfIn PDF document text
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607127fc6f877---vobaputemebinumifejotusa.pdfIn PDF document text
    • http://grupogmec.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b88421e29d---binawijivagikovirod.pdfIn PDF document text
    • https://bataretak.com/img/files/file/wagetebarifiponoterekotaf.pdfIn PDF document text
    • http://suaups.net/userfiles/file/35077723286.pdfIn PDF document text
    • http://hotspot-usa.com/js/upload/files/sokisunetifipawatixo.pdfIn PDF document text
    • https://agrotehholding.ru/wp-content/plugins/super-forms/uploads/php/files/019796280b20cee46ac455bc38ce7b47/36532410290.pdfIn PDF document text
    • http://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/ehio14mfg2cjt81rgtlrm9bk13/24200957869.pdfIn PDF document text
    • http://xn--lv0az70cxar.tw/uploads//files/202108091910394266.pdfIn PDF document text
    • http://dawahcity.com/userfiles/file/49935097369.pdfIn PDF document text
    • http://changrung.com/ckfinder/userfiles/files/53029108904.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4e579713f0---fetifazolenixatokudolofud.pdfIn PDF document text
    • http://ttlengenharia.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16075f7a6e08d6---dafiwesutoworug.pdfIn PDF document text
    • http://rainternacional.com/userfiles/file/vowebajimulidival.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=rachel+carson+silent+spring+book+pdfPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000121cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121CC 11176 bytes
SHA-256: edc9e9b06ba68c902441b32ee1164eb934d1ae0e56bcee4c187d44ac0f003e1b
font_01_sfnt_off00013b78.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B78 17716 bytes
SHA-256: 7a8f51de9546864055f3eeece6d623d365c968e1efa3e72b5e1a302530d091b7
font_02_sfnt_off00016980.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16980 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1