Malicious PDF — malware analysis report

Static analysis result for SHA-256 136c74e820fc1598…

MALICIOUS

PDF

83.5 KB Created: 2021-09-11 07:49:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: cfacb42c4a589c61ae8ea8dc99ceb020 SHA-1: 48087ea483173418320134a303b87557de2322bf SHA-256: 136c74e820fc1598f16bf2a7e5543c0cbcb2109a5bb9755710ec24d1ff3c21f4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1055.012 Process Injection

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS upload storage and disposable hosting, suggesting it's designed to redirect users to potentially harmful sites. The presence of multiple unknown URLs further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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 https://nikolsbeauty.com/webroot/f/uploads/file/44082187567.pdf In PDF document text
    • https://unique-u.biz/images/uploads/file/rovobatoxikisuponugur.pdfIn PDF document text
    • http://efcosmetic.com/uploadfile/files/6488984740.pdfIn PDF document text
    • http://bagandpack.ru/wp-content/plugins/super-forms/uploads/php/files/4c60722a8e509d5a0052a755c67bc836/nasotubuk.pdfIn PDF document text
    • http://ecme.site/2015/vat/upload/files/44046051865.pdfIn PDF document text
    • https://cortemadera.com/wysiwygfiles/file/92557397428.pdfIn PDF document text
    • http://bibliotekaszamocin.pl/img/upload/files/mivotuvirowilaxoziporusel.pdfIn PDF document text
    • http://wx-test.com/upload/ckimg/files/202109110502095363.pdfIn PDF document text
    • http://liqaa-lb.com/files/userfiles/files/12164176844.pdfIn PDF document text
    • http://biolabsrl.org/userfiles/files/62869101475.pdfIn PDF document text
    • http://letnipohar.cz/upload/file/kelutasefozasiguzupab.pdfIn PDF document text
    • https://chv.vn/userfiles/file/28581855225.pdfIn PDF document text
    • https://robert-zauer.cz/userfiles/file/25290845738.pdfIn PDF document text
    • http://teormech.ru/teormech/usrimg/file/bozinibaxutixalizadu.pdfIn PDF document text
    • https://preprodpcb.com/userfiles/files/vitoluget.pdfIn PDF document text
    • https://www.marbelitesa.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16131ce31b3ece---lozivumiz.pdfIn PDF document text
    • https://lanjutpt1.com/contents/files/88789185806.pdfIn PDF document text
    • https://autotrilogy.com/wp-content/plugins/super-forms/uploads/php/files/164fb46996497ef312e0eaa19cec4799/femavegudosidagi.pdfIn PDF document text
    • http://yanarfabrics.com/firma/files/38445023166.pdfIn PDF document text
    • https://ssekolkata.com/ckfinder/userfiles/files/41305553474.pdfIn PDF document text
    • http://kernenshepler.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/nazobuweru.pdfIn PDF document text
    • http://www.saraviation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613c24788431f---45828754370.pdfIn PDF document text
    • http://mdbim.pl/ubezpiecz/obrazy/file/52150550714.pdfIn PDF document text
    • http://bkdesign.ee/userfiles/file/50295038133.pdfIn PDF document text
    • https://izometal.net/mm/file/1612552424.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=android+figma+templatePDF 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_off0000dfb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFB2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f7c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7C9 10656 bytes
SHA-256: 57394570fd84d8a7278e62cadae5a458e5b0bfb570f6e27a1c44e2a1b5c064ae
font_02_sfnt_off00010fed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FED 18984 bytes
SHA-256: 75e4bbb8a6ea095de4b04778317d16fc750cb5cd4071f6a004955abda1458901