Malicious PDF — malware analysis report

Static analysis result for SHA-256 4c4e8f469c8c44db…

MALICIOUS

PDF

74.4 KB Created: 2021-04-12 11:51:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: 5399837d3ac673c269dfa83d48e55f87 SHA-1: e76d77360f514fc4b062f88487ada5b6259a54ca SHA-256: 4c4e8f469c8c44dbb303ec228ec94b9c1b9a77c313fae872106b08c310e624bd
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to suspicious domains and are structured to appear as legitimate document downloads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest an attempt to redirect the user to a malicious site, potentially exploiting vulnerabilities or delivering a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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 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 http://www.muttypawsacademy.com/sites/default/files/webform/vaccines/taxevoxasubosiwugudabi.pdf In PDF document text
    • http://oaklandchildcare.org/sites/default/files/webform/1289321409.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/53132673180.pdfIn PDF document text
    • https://www.newburghgroup.com/sites/default/files/webform/resumes/falaburisidibiwad.pdfIn PDF document text
    • http://russian-ice-spb.ru/sites/default/files/webform/files/fapulewamekunasu.pdfIn PDF document text
    • http://www.pbttphtk.gov.my/sites/default/files/webform/31626011693.pdfIn PDF document text
    • http://www.grotekeukens.be/sites/default/files/webform/gmawards2018/84972388600.pdfIn PDF document text
    • http://seiary.com/sites/default/files/webform/rec/jizexatunurometubukos.pdfIn PDF document text
    • http://www.sumnercountyhospital.org/sites/default/files/webform/xubapubawaral.pdfIn PDF document text
    • https://www.afscme65.org/system/files/webform/11173368180.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/zozagosetimof.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/buvonajevomowetizebijix.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=san+pedro+cactus+identificationPDF link annotation
    • https://lib.asu.edu/system/files/webform/rutepirunumobapof.pdfIn PDF document text
    • https://www.ice.cam.ac.uk/sites/www.ice.cam.ac.uk/files/webform/xegenaxug.pdfIn PDF document text
    • https://campusrec.princeton.edu/system/files/webform/7624886728.pdfIn 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_off0000e78d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE78D 5220 bytes
SHA-256: f6320e9fb6d3fb4e2872cfdc9f5baad89c7d0a63599ea8b19f6c4b258d2d73d7
font_01_sfnt_off0000f95c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF95C 10464 bytes
SHA-256: cec3adaecf91bdb9ac78ba06eef70ecf13f712583ad3ac0eee2bc252a3f00639