Malicious PDF — malware analysis report

Static analysis result for SHA-256 1f84b817a00a0f70…

MALICIOUS

PDF

69.3 KB Created: 2021-01-04 02:36:27 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: 36daac084b982933feb9efc9f1dd689d SHA-1: cf636b3ffbb1eb30021c167c3938836610ccdbb2 SHA-256: 1f84b817a00a0f700c1628c5279b7d052819e21ea678c2ea34c5ebfa2b18319d
96 Risk Score

Malware Insights

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

The file is a PDF containing an embedded URI pointing to a suspicious domain, identified by ClamAV as Pdf.Phishing.Trojan. The document body, though heavily obfuscated, contains text related to 'genetics problems' and 'worksheet answers', suggesting a lure to trick users into visiting the malicious URL. The presence of embedded URLs and the ML classifier's high confidence score indicate a malicious intent, likely for phishing or to serve a secondary payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 4

  • 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://traffnew.ru/123?utm_term=genetics+problems+abo+blood+groups+worksheet+answers PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4382958/normal_5f8d04426f75c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4450354/normal_5fc2038cdbaee.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4388833/normal_5fea3ee7e7c2d.pdfIn PDF document text
    • https://cdn.sqhk.co/juxerawabuf/IijhaOY/soxazimabuvolar.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405907/normal_5fb419af5a56b.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374175/normal_5f8b9d783ad77.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4365624/normal_5fd083fd3cc2a.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/2e0dc08d-cae1-48f9-bad0-f3e4d1ce49f5/2003_mercedes_benz_ml350_owners_manual.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/baa6801b-05c0-4e19-97c9-0eabb4267afa/modolebabinubutepitiv.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c140917e-1ff1-43a7-8c2f-5cca7c5f1b8a/briggs__stratton_repair_manual_free_download.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/257e6521-5236-46e1-b337-a35b24c8f82c/70419653854.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1b6635b5-68f5-410d-8434-42e38fcf70e6/crosman_38c_parts_diagram.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_off0000cf55.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF55 5812 bytes
SHA-256: c1c7bac14950fc24f94be411073ae3d04cca9218923fb8567d02dde1a41ce78d
font_01_sfnt_off0000e2ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2FF 10692 bytes
SHA-256: 84c39d47bb3f587ef07731a5987c23bb9c0bf658cf50183f452b5732e15e5610