Malicious PDF — malware analysis report

Static analysis result for SHA-256 af43c115065cd238…

MALICIOUS

PDF

82.5 KB Created: 2021-06-01 20:10:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: ea4e80512d16e4660b938a354edecf29 SHA-1: 72a8a8d3353d52ad3b75fc482587b9d215bfb8fb SHA-256: af43c115065cd238791020e3ec4b4b93e6f114b4655c71cca2ec253478399e51
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 hosted on disposable domains, indicating a link farm or SEO manipulation tactic. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution via the linked PDFs. No scripts were extracted, but the PDF structure itself facilitates the attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://resalured.ru/123?utm_term=cloud+atlas+piano+sheet PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4489244/normal_605aadca9a0d1.pdfIn PDF document text
    • https://wegesunovajoj.weebly.com/uploads/1/3/4/8/134887244/47eb188baac27.pdfIn PDF document text
    • https://static.s123-cdn-static-d.com/uploads/4470389/normal_60b06bf6d0c3d.pdfIn PDF document text
    • https://nawawuxilebop.weebly.com/uploads/1/3/4/6/134679594/mopisaguro.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4501374/normal_5ffa6c53b85d9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370317/normal_604b6ffa9ae5b.pdfIn PDF document text
    • https://zevigetadafuwun.weebly.com/uploads/1/3/0/9/130969942/norebenapivo-gilijaguwifed-nudafifadup.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4484835/normal_5fee33fc1bb56.pdfIn PDF document text
    • https://vajemedodumuni.weebly.com/uploads/1/3/4/3/134351385/zerin.pdfIn PDF document text
    • https://wunenogapo.weebly.com/uploads/1/3/4/5/134509221/jifibul.pdfIn PDF document text
    • https://gitapobukelagij.weebly.com/uploads/1/3/4/2/134266265/kapatur_lobuluvofusip_vazilesikinarin.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416923/normal_5fd33ab74645c.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4466161/normal_5fe0cd1fb677a.pdfIn PDF document text
    • https://vugaxedugu.weebly.com/uploads/1/3/5/9/135971543/lamaduxise.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4449183/normal_5ffc846a6e12f.pdfIn PDF document text
    • https://joxisewegiwazev.weebly.com/uploads/1/3/4/6/134669132/xunogavut-wuzawu.pdfIn PDF document text
    • https://sakolepak.weebly.com/uploads/1/3/4/5/134588428/zodufitusivo.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4368999/normal_5fe3db5ae1f59.pdfIn PDF document text
    • https://xexibuwowixuzu.weebly.com/uploads/1/3/4/4/134455615/demeb-zipiwokir-jobobogu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/e1cc93d0-06ef-44ff-ba2c-15b1b5908b86/29772841643.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/215cfaa2-73ab-4a71-a51e-82a1014fc376/no_game_no_life_fanfiction_sora_x_shiro_lemon.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0e624717-9fe9-4474-bc96-3b190f5951f0/35564417814.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6410e000-b724-4279-9bd4-37d53f3e49fb/how_to_write_an_academic_intervention_plan.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bdddaafe-8879-4439-ae5b-0642b1b8f196/does_walmart_carry_landline_phones.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_off0001038a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1038A 4856 bytes
SHA-256: bdbb66013a80352edbdb411b96ec1e83ea5cd4aad87cda578647f91e45011824
font_01_sfnt_off00011405.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11405 12072 bytes
SHA-256: a1b8990a6d82ca8009e5ce2e33fd3420c997f97ed5e0f5c25771fb0d5c88aed2