Malicious PDF — malware analysis report

Static analysis result for SHA-256 4abd649c11eff278…

MALICIOUS

PDF

80.0 KB Created: 2021-05-29 09:53:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 9bcadb98b72ff8093899939ffb9222ef SHA-1: 96f479272d875eecd6f2b89bb245ff91818075e9 SHA-256: 4abd649c11eff278d211cb32c130908dd4ec23564b8f69299ec5891518c8e22b
156 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, identified as a link farm, suggesting a malicious intent to redirect users. The ClamAV detection and ML classifier strongly indicate malicious content, specifically phishing. While no scripts were explicitly extracted, the PDF structure and numerous embedded URLs point towards a tactic of redirecting users to potentially malicious sites, likely for SEO spam or phishing purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://ponafet.ru/strik?utm_term=exercise+on+compound+adjectives+for+class+5
    • https://static.s123-cdn-static.com/uploads/4481273/normal_600025246b69c.pdf
    • https://cdn-cms.f-static.net/uploads/4387718/normal_6047890acf898.pdf
    • https://cdn-cms.f-static.net/uploads/4465555/normal_60659d1e53565.pdf
    • https://cdn-cms.f-static.net/uploads/4421474/normal_604067d37c823.pdf
    • https://static.s123-cdn-static-d.com/uploads/4366316/normal_60b0baae6f943.pdf
    • https://cdn-cms.f-static.net/uploads/4385020/normal_601484e416f1f.pdf
    • https://static.s123-cdn-static.com/uploads/4444378/normal_5fdda01e69f23.pdf
    • https://ribovaboj.weebly.com/uploads/1/3/0/7/130775049/gidatilalil.pdf
    • https://cdn-cms.f-static.net/uploads/4369158/normal_601c6b126365e.pdf
    • https://static.s123-cdn-static.com/uploads/4460473/normal_5fe46d38bc0f2.pdf
    • https://cdn-cms.f-static.net/uploads/4489994/normal_601e23fd6d8d1.pdf
    • https://nazutusimeraj.weebly.com/uploads/1/3/4/8/134883567/9148391.pdf
    • https://gisidamuxifa.weebly.com/uploads/1/3/0/7/130775495/7135393.pdf
    • https://gozowejikagigu.weebly.com/uploads/1/3/5/3/135345496/d50b1fe978.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/a363f61d-7220-4a00-aaf7-6b64828a153f/11666060547.pdf
    • https://uploads.strikinglycdn.com/files/38615020-9ac5-4cff-9063-0a2d8ddc970d/39135150281.pdf
    • https://uploads.strikinglycdn.com/files/4d41d38a-5333-4d55-86b9-3aa0b01cd106/roku_express_3900x_airplay_2.pdf
    • https://uploads.strikinglycdn.com/files/6216e8d8-b9d3-4374-a3bc-452c62b56d1b/adobe_photoshop_premiere_elements_2021_winde_download_full_version.pdf
    • https://uploads.strikinglycdn.com/files/11888017-c175-4ca9-bb0d-69c885e0f3c7/biwatujibebegajefug.pdf
    • https://uploads.strikinglycdn.com/files/8ee10fbf-921d-495d-8aea-914e6c6f8ef4/nimiduvaketej.pdf
    • https://uploads.strikinglycdn.com/files/2aeecf49-225f-49b2-9277-1c28fd55036c/husqvarna_chainsaw_455_rancher_vs_460.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f7dd.bin
6a138799909a1b665250b29fb273b427c082d7ebba3059817f404a80d31de78e
pdf-font-stream PDF embedded font (sfnt) at offset 0xF7DD 5584 bytes
font_01_sfnt_off00010adf.bin
2c2d9e35efd724887f9bf195f7f765e514d6fea9ce004a4251ec76422d6b32ca
pdf-font-stream PDF embedded font (sfnt) at offset 0x10ADF 11144 bytes