Malicious PDF — malware analysis report

Static analysis result for SHA-256 687119a7e3e24be3…

MALICIOUS

PDF

73.9 KB Created: 2021-03-05 17:37:49 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: 173d58492423ab08cab3935963749b4c SHA-1: 3a6fbbb1af628424b5a3078db8df905028cbce70 SHA-256: 687119a7e3e24be30188227bf6e51bfa60c967773f65ae4cef52b73d3e02ce6d
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or phishing attempt. The ML classifier and ClamAV detection strongly indicate maliciousness. While no scripts were explicitly extracted, the PDF structure and heuristics suggest it's designed to redirect users to malicious websites, potentially for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • 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.
  • 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/wix?keyword=gregg+college+keyboarding+%2526+document+processing+11th+edition+pdf PDF link annotation
    • http://inter-kalinka.ru/calorimetry_lab_burning_a_peanut_answerslavrq.pdfIn PDF document text
    • https://siximegam.weebly.com/uploads/1/3/1/4/131453251/vorogoviwul.pdfIn PDF document text
    • https://bejutenexej.weebly.com/uploads/1/3/3/9/133997629/gakuberiravo_vakibevodulo_nokiletaxotunog_topinanopugofo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4499283/normal_600ffbf8e4c7c.pdfIn PDF document text
    • http://mynasert.online/tawafowanidapixasomatozum5k.pdfIn PDF document text
    • http://wppremium.org/descriptive_accounting_free_downloadto8yh.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4452861/normal_600ec25408a9c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4408464/normal_600ece935e9f8.pdfIn PDF document text
    • https://puxefulido.weebly.com/uploads/1/3/1/3/131383426/pabuwosa_luzazezepoxoz.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4453332/normal_6032b16d6e9e1.pdfIn PDF document text
    • http://white-x.fun/leawo_registration_code_freef2md6.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/kiguteperilodu/89173058905.pdfIn PDF document text
    • https://bb55feb6-a0c4-48ae-8f72-aea2c45912f8.filesusr.com/ugd/b9801a_e894a469bc0247979ad9accbbfcbb4ff.pdf?index=trueIn PDF document text
    • https://08202b68-adf4-4b7d-bb06-fcebe54c78b8.filesusr.com/ugd/76dd3d_0980c9ac274e496a98c80160eb82ad49.pdf?index=trueIn PDF document text
    • https://02664c88-84e5-42fa-aae3-682d3a0d4328.filesusr.com/ugd/39d081_1ab91e9c756743c58c95cc85b03d47d9.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/vavejijitatofu/mat-_autocomplete_custom_template.pdfIn PDF document text
    • https://s3.amazonaws.com/mudurixo/hd_blue_blur_background.pdfIn PDF document text
    • https://238a82c5-85a8-4641-a991-2f0f5270ddc4.filesusr.com/ugd/63f22d_06db2bc8725c44c09c76d0399c150030.pdf?index=trueIn 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
    • 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_off0000cf5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF5B 5264 bytes
SHA-256: 25e3d0e72995c9919b5164c5f5663b314d885bdb0d588c20b847ac59b8c1fd72
font_01_sfnt_off0000e160.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE160 10548 bytes
SHA-256: 5ef8457eaa745a6fd80aa6f3cee44a48020cf3f214df615e30c1ad4ac3ba2760
font_02_sfnt_off000105b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105B7 16084 bytes
SHA-256: 3dd6252bb62cdcc21e2b76bdeb68ba6c8db9c2d08edae94764e010183c5b1848