Malicious PDF — malware analysis report

Static analysis result for SHA-256 452fa0c191d52ff7…

MALICIOUS

PDF

75.4 KB Created: 2021-04-07 16:15:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: 665be1384498c407bf517954f7b09e2d SHA-1: 99d941125b55691578d3ea5513f2d7d6c1617b66 SHA-256: 452fa0c191d52ff73d784506a53e7e07eeb65c6a1b9cdffaec3d1f2e7cdd01a8
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains a large number of external links, many pointing to disposable hosting, suggesting it is part of a link farm designed to drive traffic to potentially malicious sites. The document body, though heavily obfuscated, contains text related to cleaning clock movements, which is likely a lure to disguise the malicious nature of the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://kuzutuzo.ru/strik?utm_term=how+to+clean+a+clock+movement PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4497348/normal_5fd7c14a96f63.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476782/normal_60295244e741b.pdfIn PDF document text
    • http://xuzejomuxide.22web.org/formica_laminate_sheets_ireland.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4410217/normal_606048a5f1b78.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4527164/normal_5fca90dc0711c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4464702/normal_600d48840a3ca.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448724/normal_605600be84124.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4421629/normal_6012c25e4da55.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/8816b346-9aad-45df-a8d4-78b72df5f907/86659448115.pdfIn PDF document text
    • http://samipada.epizy.com/44641124911.pdfIn PDF document text
    • https://711a90e7-97f2-4eab-8690-3003ec1e9b64.filesusr.com/ugd/a0905b_10ad7b328c34412b9e0db028c82e0f1d.pdf?index=trueIn PDF document text
    • https://f6ce3cfb-f922-470c-9e0e-eaf724001b0e.filesusr.com/ugd/defcb2_6e273077ced449aa87155687be1b0789.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/948b56c6-d785-4288-8a48-75b107b0798f/77511436253.pdfIn PDF document text
    • https://84bd2c60-91d0-47b6-9565-6ae8a6593e58.filesusr.com/ugd/963627_e54e8328f92a42a99eaa5a83962c0ee5.pdf?index=trueIn PDF document text
    • https://6ec3981f-6443-463b-a164-91fc69f101d9.filesusr.com/ugd/7603ae_786ca8877c2146cea304a731f1c21fba.pdf?index=trueIn PDF document text
    • https://d5fb4b5d-766d-4e54-ab1c-ecc61d2b7d82.filesusr.com/ugd/b0c8dc_a92aae634de04ef59c2a905cc3175123.pdf?index=trueIn PDF document text
    • https://1d942ef5-affb-47d8-8f99-70a3d187b733.filesusr.com/ugd/3283b0_800b683aa01f49aca6f86495c4ea4ed5.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/7685a627-2c83-4d30-ad75-bb96d1bd3fdd/xuturadulefikiluxufapega.pdfIn PDF document text
    • http://tuvaditeli.rf.gd/numotosibizesilomof.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_off0000ec59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC59 4848 bytes
SHA-256: e4721276412075163c96dabea15687f7d2aee53c090fdebeab1265a29bfd3c1c
font_01_sfnt_off0000fce0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCE0 10468 bytes
SHA-256: 498b622efdc559b8555464c3b218180f46125a558d15daa72a76cab275eee654