Malicious PDF — malware analysis report

Static analysis result for SHA-256 99f824019f83978a…

MALICIOUS

PDF

84.0 KB Created: 2021-05-25 09:45:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: b0e8fab06c2407f5f1902aad3a76be39 SHA-1: f97544fee46194eb46001c2fdbc5ab8f5ee4c20b SHA-256: 99f824019f83978acc6f0e0ccd5ced5537169c5dede3d15f8cdd543a46f31e87
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to PDF files, suggesting a link farm or SEO manipulation tactic. The primary URL, 'https://crophysi.ru/strik?utm_term=kaatre+en+vaasal+vandhai+flute+ringtone+mp3+download', is presented as a download for a flute ringtone, which is a common lure for phishing or malware delivery. ClamAV and ML classifiers also flagged this PDF as malicious, specifically as a phishing trojan.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://crophysi.ru/strik?utm_term=kaatre+en+vaasal+vandhai+flute+ringtone+mp3+download
    • https://cdn-cms.f-static.net/uploads/4385613/normal_602867cddf4ad.pdf
    • https://cdn-cms.f-static.net/uploads/4455902/normal_6055ae60efab1.pdf
    • https://vafopizinenited.weebly.com/uploads/1/3/4/4/134480139/kodenif.pdf
    • https://cdn-cms.f-static.net/uploads/4469850/normal_604cd756984ed.pdf
    • https://vumevomuw.weebly.com/uploads/1/3/4/3/134335884/rugabogolos.pdf
    • https://cdn-cms.f-static.net/uploads/4382614/normal_603ce4b858616.pdf
    • https://cdn-cms.f-static.net/uploads/4365599/normal_602e000bb0cad.pdf
    • https://static.s123-cdn-static.com/uploads/4365642/normal_5fecaea250a1c.pdf
    • https://cdn-cms.f-static.net/uploads/4494417/normal_601e4d7f6e552.pdf
    • https://cdn-cms.f-static.net/uploads/4478950/normal_604d758c0d230.pdf
    • https://cdn-cms.f-static.net/uploads/4370737/normal_6056f0b39b139.pdf
    • https://cdn-cms.f-static.net/uploads/4367310/normal_60442ee0e759e.pdf
    • https://cdn-cms.f-static.net/uploads/4466680/normal_604c9d7cc3791.pdf
    • https://vabakapis.weebly.com/uploads/1/3/1/4/131453405/d118b74d561b4.pdf
    • https://static.s123-cdn-static.com/uploads/4476569/normal_5fc833a72f56b.pdf
    • https://cdn-cms.f-static.net/uploads/4375093/normal_60602eb7a678c.pdf
    • https://kasureketox.weebly.com/uploads/1/3/4/8/134856927/5395810.pdf
    • https://cdn-cms.f-static.net/uploads/4377935/normal_603b517718648.pdf
    • https://static.s123-cdn-static.com/uploads/4388048/normal_5fc721024f038.pdf
    • https://static.s123-cdn-static.com/uploads/4470385/normal_6008d49dcce8d.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/619f1332-2865-49e4-97e9-0bebf16e2808/what_is_shadow_work_spiritual.pdf
    • https://uploads.strikinglycdn.com/files/3ddf5adc-0640-4d13-b5aa-0d42499c1249/jutivuviwusugip.pdf
    • https://uploads.strikinglycdn.com/files/22076994-1fe2-4823-b5a3-aee2ab3cbee3/japorawazisola.pdf
    • https://uploads.strikinglycdn.com/files/6d6c2c1d-7033-4e03-897d-6566cce74f52/15950594079.pdf
    • https://uploads.strikinglycdn.com/files/52a215eb-5ec4-41b5-9ed1-3fc523a623be/67863277221.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
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ead1.bin
a1b61cd4a23e26e08a9cf1e83b4b0a7bb69964d285d99adad84ac5ec94f79e98
pdf-font-stream PDF embedded font (sfnt) at offset 0xEAD1 5740 bytes
font_01_sfnt_off0000fe47.bin
a6380d476d870b736758e1e7e8de8e2045843b1517103fe5f90e8bf683aab298
pdf-font-stream PDF embedded font (sfnt) at offset 0xFE47 1596 bytes
font_02_sfnt_off0001066b.bin
25cff79d6000b659e6d18db4c957dc68299dd2c3851de08e7d6f44cb85361f2e
pdf-font-stream PDF embedded font (sfnt) at offset 0x1066B 11208 bytes
font_03_sfnt_off00012cdd.bin
dcc437beaabc532c244cb2402c7e187dabb6fccd34af89cd9e2270a2a4498d3d
pdf-font-stream PDF embedded font (sfnt) at offset 0x12CDD 16168 bytes