Malicious PDF — malware analysis report

Static analysis result for SHA-256 11ef6fd35f07c951…

MALICIOUS

PDF

84.4 KB Created: 2021-06-25 12:07:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-20
MD5: 7dead733b988afba3235a8a8a8b48fd8 SHA-1: d4917f2448131d22b10dc74eb278f854531b9716 SHA-256: 11ef6fd35f07c9510ca6c5224777dc12f20d2fb2d001edc9fa524dfdbbd7668c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, many pointing to compromised WordPress sites, suggesting it's designed as a link farm to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of multiple external URIs and link farm heuristics confirms the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://www.tctnanotech.com/wp-content/plugins/super-forms/uploads/php/files/09fd2a24c4f81920fd64d8d29b4c6c7e/kolivoge.pdf In PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608c25de452fb---woxubapusipag.pdfIn PDF document text
    • https://ohligschlaeger-berger.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b2e1afd4e10---juxifem.pdfIn PDF document text
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/maxobutamala.pdfIn PDF document text
    • http://ciaooo.ru/uploades/userfiles/file/gefapemo.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1612a36e58---kitoregunase.pdfIn PDF document text
    • https://burkina-businessschool.com/business_school/uploads/file/ritunimevezamesefopezov.pdfIn PDF document text
    • https://veglifekc.org/wp-content/plugins/super-forms/uploads/php/files//sixipajorugoxebosu.pdfIn PDF document text
    • http://mirandatutoringcentre.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16072a3e21895f---85548700466.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/16089bcd831436---43533814087.pdfIn PDF document text
    • https://dermo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160881fa79984d---losozape.pdfIn PDF document text
    • https://lakeshoresmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/qu0kcvarlbme63hbnhufp57qq1/jazonejofebigomuk.pdfIn PDF document text
    • https://mzlpro.com/web/img/podborky/files/1323721362.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/t760sbjr3eq1n6imh6uj14kpg0/31468186123.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607c2ffb985d9---65190211269.pdfIn PDF document text
    • http://xn--e1aaafipco3bk8gra3b.xn--p1ai/upload_picture/file/71095982615.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=rena+xp2+manualPDF 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_off0000e6ca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6CA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fedc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEDC 18056 bytes
SHA-256: f75d8aacba10db12a10d14e1752c4976972c9bc6cf503e9bbfd8d1e19ed42555
font_02_sfnt_off00012e82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E82 10204 bytes
SHA-256: 0034cd4fd9f8538c9b8f9889631c4c21449eec4a5fccda2518a9656adb0291a4