Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8540add5ef61970…

MALICIOUS

PDF

75.9 KB Created: 2021-06-09 04:09:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: c8db8d5a3644e519fd78480e4fd64cfd SHA-1: 3dc98bc7fbfcb32c409244290d1d9a1a96cf8641 SHA-256: c8540add5ef61970880c08ecdb2de01c1c2a5cc5cb6046e9928c293270cdcd71
194 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, many hosted on disposable domains, indicating a link farm or SEO manipulation scheme. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and numerous external URLs are indicative of a malicious document, potentially leading to further compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://ketchas.ru/pbw?utm_term=online+test+of+tenses+for+class+7 PDF link annotation
    • https://static.s123-cdn-static-d.com/uploads/4414851/normal_60b006ffa4381.pdfIn PDF document text
    • https://tepidopuk.weebly.com/uploads/1/3/4/6/134698813/1371eeb.pdfIn PDF document text
    • https://pumebogevi.weebly.com/uploads/1/3/4/5/134583518/d0d262c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4383160/normal_5fce4530a8d5f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4411512/normal_6038c5bb89158.pdfIn PDF document text
    • https://zovezeko.weebly.com/uploads/1/3/4/6/134697242/8782575.pdfIn PDF document text
    • https://vudelugofede.weebly.com/uploads/1/3/4/3/134383428/minolelunim.pdfIn PDF document text
    • https://bedasalisavif.weebly.com/uploads/1/3/4/6/134601990/tegejikesorom-juvusi-kozozemorofo.pdfIn PDF document text
    • https://tefuledajejus.weebly.com/uploads/1/3/1/4/131437322/1897811.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4376869/normal_6022b36912002.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368977/normal_605b810de8c6d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4466408/normal_60be2a4f8e4be.pdfIn PDF document text
    • https://dulewexafup.weebly.com/uploads/1/3/4/7/134702005/ledizasolagusepaj.pdfIn PDF document text
    • https://bamegipizof.weebly.com/uploads/1/3/4/6/134647446/poniwe-gozamiwijipara-jejiviwe.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4377656/normal_60b003b247d90.pdfIn PDF document text
    • https://woperuxotuxolo.weebly.com/uploads/1/3/4/8/134849923/wexevusaz.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4387825/normal_5ff19c5437545.pdfIn PDF document text
    • https://lafasisagugugup.weebly.com/uploads/1/3/1/6/131637889/9237323.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4415739/normal_6064b89419d68.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4482848/normal_606633ff206d0.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4418575/normal_603735534b130.pdfIn PDF document text
    • https://mimuromujalu.weebly.com/uploads/1/3/0/7/130739347/6870782.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374954/normal_60519ca12335e.pdfIn PDF document text
    • https://tavikumor.weebly.com/uploads/1/3/4/4/134476146/4368932.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000eace.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEACE 4980 bytes
SHA-256: 5c458cd2b1a077c36a519c3999f22be38dd0809d79d35e41da6d7ef3a0dcbae1
font_01_sfnt_off0000fbd5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFBD5 11208 bytes
SHA-256: ee706c70fee6bb52787c43920256ad544c6df5ade99295052cff18963bf4d3e8