Malicious PDF — malware analysis report

Static analysis result for SHA-256 bffeb2bb0d57a175…

MALICIOUS

PDF

77.1 KB Created: 2021-03-30 06:41:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 6c299acde70e0093b6ffee78df7c24f9 SHA-1: 22b18b1e8c0be97906a530c05c220bc59f426a14 SHA-256: bffeb2bb0d57a17595c05b28c2bdfcc23454041e1e43ead040babd325efc42ed
156 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ClamAV and an ML classifier, exhibiting characteristics of a link farm. It contains numerous external URIs, with a critical heuristic firing for a mass external PDF link farm. The primary malicious URL identified is https://nipisod.ru/wix?keyword=nevermore+rwby+lyrics, suggesting a potential phishing or SEO spamming campaign. No scripts were extracted, but the PDF structure itself facilitates the attack by linking to external content.

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://nipisod.ru/wix?keyword=nevermore+rwby+lyrics
    • https://cdn-cms.f-static.net/uploads/4423460/normal_601b4bd9432b3.pdf
    • https://nebobaxewakizix.weebly.com/uploads/1/3/1/6/131637309/nevodup_giniropuvilixuf_bufuxex_vamakaxa.pdf
    • https://nawexolaka.weebly.com/uploads/1/3/4/7/134704757/e8918ba91d.pdf
    • https://masudokunu.weebly.com/uploads/1/3/4/7/134731157/woxodubib-bivugobuzoteda.pdf
    • http://zuzorovix.scienceontheweb.net/bharathiar_university_bcom_books_download.pdf
    • https://gabejopow.weebly.com/uploads/1/3/4/5/134597712/jekuzipuk.pdf
    • https://static.s123-cdn-static.com/uploads/4366381/normal_5ff9293d4e7db.pdf
    • http://tokesuditetu.getenjoyment.net/3d_reader_for_windows_10.pdf
    • http://niluwipewuxasa.medianewsonline.com/sivavijisodazebesam.pdf
    • https://cdn-cms.f-static.net/uploads/4365567/normal_5fd2a7eaf0e85.pdf
    • https://mabaxezo.weebly.com/uploads/1/3/4/7/134766945/7082292.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://s3.amazonaws.com/bewibiwat/28883645858.pdf
    • https://56a79910-2d97-40e4-a1df-bca3b17021d7.filesusr.com/ugd/2721fc_8d76faec0c9c4aaab47aed699b959b1a.pdf?index=true
    • https://f1ddcea9-c323-452c-a4d3-aaefec61e50a.filesusr.com/ugd/defd8a_00439b54225f4e9aa7e7ebea571aa877.pdf?index=true
    • https://s3.amazonaws.com/xarojapi/10494733589.pdf
    • https://s3.amazonaws.com/tunenijexe/tobofaxobovabowedumefiti.pdf
    • http://wovuluvoju.onlinewebshop.net/23624384569.pdf
    • https://fccd5518-64e1-462d-9dbe-8d8d8a19ca7a.filesusr.com/ugd/eb005d_aadf9c998f57460e959b94c6c70ed80a.pdf?index=true
    • http://domuromu.atwebpages.com/6815645458.pdf
    • https://9c43cb74-45e3-47de-9527-fda2e8336169.filesusr.com/ugd/af0aa9_afaf72434dba4378ad41ccb0f1718956.pdf?index=true
    • https://141ebdc9-a3c9-4c6d-b8f9-366dbf139dec.filesusr.com/ugd/46bfb0_8146fa6e47ec4a9abab343f93f4d912e.pdf?index=true
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e524.bin
b78d5cfdb4fafa9e402abcac07cbdd2ddeca5cbfb2f592e56492d44517c6ed8c
pdf-font-stream PDF embedded font (sfnt) at offset 0xE524 4700 bytes
font_01_sfnt_off0000f52d.bin
3d899254a5df92a1be6bafda7ee2a202bfadad16eaba954fccb2e0d01c051073
pdf-font-stream PDF embedded font (sfnt) at offset 0xF52D 10752 bytes
font_02_sfnt_off00011a1b.bin
9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A1B 4324 bytes