Malicious PDF — malware analysis report

Static analysis result for SHA-256 33a45b7f981d6bf9…

MALICIOUS

PDF

85.1 KB Created: 2021-02-21 21:37:42 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 5dc84cea1557d14314cb48270a2f469a SHA-1: ff23fe67467ffb7cf997427f42eb2f2d4c580c9f SHA-256: 33a45b7f981d6bf9fff6da111a34994ef9d2dce1a2d8b7675cbe19f2bb2ab26b
246 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical finding for brand-impersonation credential phishing. The ML classifier also returned a high confidence score for maliciousness. The document contains numerous external links, many pointing to disposable hosting, suggesting a link farm designed to redirect users to phishing sites. While no scripts were explicitly extracted, the presence of embedded URLs and the phishing lure indicate an attempt to trick users into submitting credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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.
  • Brand-impersonation credential phishing lure critical SE_BRAND_CREDENTIAL_PHISH
    Document impersonates a well-known consumer brand and uses account-security / verification language ('unusual activity', 'account on hold', 'verify your account') to steer the reader to a credential-harvesting link. Corroborated by: action link to abused redirector https://koxabiniz.weebly.com/uploads/1/3/5/9/135994092/3084065.pdf.
  • 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://jottigo.ru/strik?utm_term=touch+of+class+catalog+request PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4409420/normal_60138baf8f1da.pdfIn PDF document text
    • https://koxabiniz.weebly.com/uploads/1/3/5/9/135994092/3084065.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4384026/normal_601d938770039.pdfIn PDF document text
    • https://sujixiku.weebly.com/uploads/1/3/0/7/130739139/e2837c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4384472/normal_60035ed07f7d1.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4484114/normal_600919b18ff48.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4444852/normal_60315ae79ae65.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4410414/normal_5fe96738425c5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443624/normal_5fd2f880dfb61.pdfIn PDF document text
    • https://gijufonuvaxi.weebly.com/uploads/1/3/4/8/134874477/xadese_jibefikipiwi_jawodalunigod_fenaj.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4407988/normal_602b899712551.pdfIn PDF document text
    • https://rizafosukozesal.weebly.com/uploads/1/3/5/3/135346652/4765532.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4368964/normal_6015a9db9c9fd.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4453329/normal_5ffe08dbd6a61.pdfIn PDF document text
    • https://cdn.sqhk.co/pesuxitum/1gjhhhf/9226901809.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4444643/normal_5fe41b6bf1756.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4427091/normal_60157efc673e1.pdfIn PDF document text
    • https://ragusixiseditof.weebly.com/uploads/1/3/0/8/130814169/c584bdef8582bf.pdfIn PDF document text
    • https://cdn.sqhk.co/rejiwosujupa/hfcLigV/neon_field_hockey_sticks_near_me.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_off00010ee6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EE6 5216 bytes
SHA-256: a4eca7cae531dc532906d5d33d4b5ad6e9a8bcc6aa405c6fd8e1654da741d245
font_01_sfnt_off0001209f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1209F 11384 bytes
SHA-256: 99066cc5f89b7a762d3b409985fd66f21ee2d893806d1cdb11b507b602904ce1