Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4925a257a955fee…

MALICIOUS

PDF

76.1 KB Created: 2021-05-29 21:09:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e9808591b73b2e23e607f6bf122a394a SHA-1: 57df5a1ef3a49006dd2c6bc241e03697529d07bd SHA-256: c4925a257a955fee074ef9fd7f751f615d9be22496b3f940d81d4114d6b6fdc7
156 Risk Score

Malware Insights

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

The PDF file contains numerous external links, identified as a link farm, with one prominent URL pointing to a domain associated with phishing or malware distribution. The ML classifier and ClamAV detection strongly indicate malicious intent. Although no scripts were explicitly extracted, the PDF structure and the presence of external links suggest it's designed to redirect users to malicious sites, potentially for credential harvesting or further payload delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://dafemum.ru/strik?utm_term=album+download+sites
    • https://sagelaxun.weebly.com/uploads/1/3/4/5/134594749/4021721.pdf
    • https://cdn-cms.f-static.net/uploads/4459464/normal_6035ad2e95504.pdf
    • https://cdn-cms.f-static.net/uploads/4444649/normal_604d17fbe7d22.pdf
    • https://static.s123-cdn-static.com/uploads/4426088/normal_5fdd5f1aee282.pdf
    • https://static.s123-cdn-static.com/uploads/4421335/normal_5fcf135f407d1.pdf
    • https://cdn-cms.f-static.net/uploads/4403952/normal_600ba97156603.pdf
    • https://static.s123-cdn-static.com/uploads/4465012/normal_5fe4699f2ac5a.pdf
    • https://static.s123-cdn-static.com/uploads/4479905/normal_5fed69fe78394.pdf
    • https://static.s123-cdn-static.com/uploads/4501654/normal_5fde5a7b24b2b.pdf
    • https://cdn-cms.f-static.net/uploads/4470221/normal_600de055220d5.pdf
    • https://cdn-cms.f-static.net/uploads/4445731/normal_6063face0ceb3.pdf
    • https://cdn-cms.f-static.net/uploads/4495391/normal_603e18c80d355.pdf
    • https://maselevajaf.weebly.com/uploads/1/3/1/3/131398143/pabejajovejikubik.pdf
    • https://static.s123-cdn-static.com/uploads/4405644/normal_5febd3010d257.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/b8de931a-4395-4e74-a766-cb963556d15d/45647373127.pdf
    • https://uploads.strikinglycdn.com/files/f9890f29-8eac-45ba-b8d9-5ecad6d06cd4/livro_de_ingls_avanado.pdf
    • https://uploads.strikinglycdn.com/files/4d8446f0-bd47-4931-b13a-4c1974c20e2c/xevuxurokamanumewi.pdf
    • https://uploads.strikinglycdn.com/files/06b1985b-d09b-4de5-9e83-e5605b8d4e8c/96763254513.pdf
    • https://uploads.strikinglycdn.com/files/bfd51091-d243-4da8-acea-923de4fbb73b/34405132540.pdf
    • https://uploads.strikinglycdn.com/files/7f9eb9bf-e1e9-4fda-90eb-3c39ae8bd87b/tiwabukigunufeg.pdf
    • https://uploads.strikinglycdn.com/files/d578cf07-5187-461b-a8a6-b25733ecc737/is_the_uppababy_bassinet_worth_it.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ed0d.bin
2236a0101d287745701bbb027e9f4ff2854a9fd2cbb46f5986bd996eef612f5d
pdf-font-stream PDF embedded font (sfnt) at offset 0xED0D 5096 bytes
font_01_sfnt_off0000fe58.bin
bb97418facf1103065b5e4240e7795828402c446e8a47a8966b2533fd530156f
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE58 10900 bytes