Malicious PDF — malware analysis report

Static analysis result for SHA-256 d82cac21391a1de1…

MALICIOUS

PDF

76.2 KB Created: 2021-05-29 22:12:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-16
MD5: 7610bddb6b2c8e3d0e0eace2d33176f1 SHA-1: 27efcfebf4f2fd949f177fa30e6ba125f1bbdc73 SHA-256: d82cac21391a1de1b93bd4bc58f3ce9d820bd7ca1e2a83a17e407c5ca7b706c0
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many of which point to disposable hosting services, suggesting a link farm designed to distribute traffic or host malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the presence of numerous external links implies an attempt to redirect the user to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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/strik?utm_term=ejercicios+de+operaciones+combinadas+para+6to+grado+de+primaria PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4464072/normal_60289e1c0958e.pdfIn PDF document text
    • https://soremasev.weebly.com/uploads/1/3/4/7/134716172/8856489.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374178/normal_605a562c47609.pdfIn PDF document text
    • https://javodamujuwevef.weebly.com/uploads/1/3/4/4/134446411/a1ff14.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4368976/normal_5fddcff6f3c34.pdfIn PDF document text
    • https://ditaluli.weebly.com/uploads/1/3/5/3/135325413/zotogewudofixafudola.pdfIn PDF document text
    • https://ponefapu.weebly.com/uploads/1/3/1/6/131637257/530880.pdfIn PDF document text
    • https://regifevadep.weebly.com/uploads/1/3/4/4/134476302/8680717.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4384819/normal_5fe1d9b50cdfb.pdfIn PDF document text
    • https://vimosetadasosus.weebly.com/uploads/1/3/2/7/132740377/sabitetagakop.pdfIn PDF document text
    • https://milunuxuv.weebly.com/uploads/1/3/4/5/134529922/9fd68aed9.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4385014/normal_606b3fdbdd0bf.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4454289/normal_6056545b5735f.pdfIn PDF document text
    • https://dubiroki.weebly.com/uploads/1/3/1/4/131483307/5939593.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4452381/normal_5ff7093e918e8.pdfIn PDF document text
    • https://tulejimukun.weebly.com/uploads/1/3/4/3/134399478/dabuba_rupinebis_xesarubeveroxaw.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4483610/normal_5fc7241cda827.pdfIn PDF document text
    • https://wemavepudobug.weebly.com/uploads/1/3/4/1/134108610/zorowixowewasuz.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4493891/normal_5ff3b64467dc3.pdfIn PDF document text
    • https://wigopezejab.weebly.com/uploads/1/3/7/4/137499336/4664007.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374360/normal_606d668516588.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388835/normal_602daa57a384c.pdfIn PDF document text
    • https://xemegejimeje.weebly.com/uploads/1/3/1/6/131636808/piwujojowaxo-wavimegeviloma.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_off0000e6c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6C2 5688 bytes
SHA-256: efda2de119329c339e1062da829d14407cd57e9d7992b5a0b148ca4996fae707
font_01_sfnt_off0000fa04.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA04 11740 bytes
SHA-256: 53366049efd3455ace3c1586d399be9c0205d9223d2bd6b1e5dadf2b1aa411b5