Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f5fb507a5f703ed…

MALICIOUS

PDF

74.4 KB Created: 2021-03-20 00:31:52 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 42700a77d745bd5facf9aec7b29843b3 SHA-1: 73624fb84a3b85dac9b49252de2ad2447e457366 SHA-256: 9f5fb507a5f703ed65de4e91ee6ccff6ab1c1712625d139e9dd60a4676ca3d52
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, with critical heuristics indicating it is a PDF containing a large number of external links, characteristic of a link farm or SEO spam. One of the extracted URLs, https://nipisod.ru/award?keyword=a+level+economics+revision+pdf, is suspicious and likely part of this malicious infrastructure. Although no scripts were explicitly extracted, the PDF structure and the presence of numerous external links suggest an attempt to redirect users to potentially harmful content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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/award?keyword=a+level+economics+revision+pdf
    • https://static.s123-cdn-static.com/uploads/4499999/normal_5fdda512bc0ad.pdf
    • http://jefevivavifax.scienceontheweb.net/bumajadarogemo.pdf
    • https://cdn-cms.f-static.net/uploads/4471085/normal_6011371505f99.pdf
    • https://static.s123-cdn-static.com/uploads/4407301/normal_5ffa145e230b6.pdf
    • http://tiwunevebir.22web.org/wipofowuteloge.pdf
    • http://jalazekesofijot.medianewsonline.com/85529699052.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/nademopor/93635538340.pdf
    • https://s3.amazonaws.com/fotepopunaj/9482201878.pdf
    • https://ab737b70-891a-4a1f-8db9-ee548211cb31.filesusr.com/ugd/ce14f3_8f4cc71c0c7d49a6b1639a13603838bc.pdf?index=true
    • http://tilomid.rf.gd/93279145152.pdf
    • https://s3.amazonaws.com/bezutu/9281279401.pdf
    • http://wifudozakiteg.epizy.com/monstrous_word_meaning_in_urdu_analyse.pdf
    • https://s3.amazonaws.com/bisiku/cookies_website_template.pdf
    • https://s3.amazonaws.com/gumagabu/zotajogabaderimezawegi.pdf
    • https://s3.amazonaws.com/mejobu/que_significa_palabra_languidece.pdf
    • https://s3.amazonaws.com/jidagafinuxesu/9397013972.pdf
    • http://vetovolixexa.epizy.com/baal_veer_2018_sony_pal_video.pdf
    • http://repefewuvu.epizy.com/ruvijamobepunulum.pdf
    • https://95c758d6-fd33-43c6-b5d0-f1f55e07e946.filesusr.com/ugd/cb0188_42aa3ceb67c34794a22936f4f4941479.pdf?index=true
    • https://s3.amazonaws.com/dikobepibelun/fozenuxuredarawubuj.pdf
    • https://s3.amazonaws.com/rirusozo/honeywell_thermostat_manual_rth221b1039.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_off0000e020.bin
bf49c07acb38e62ef8dc1247e006b370126927d2aebaad72aeceabba20d1c175		 pdf-font-stream PDF embedded font (sfnt) at offset 0xE020 5140 bytes
font_01_sfnt_off0000f192.bin
93ce99ba9e770a1ae17e35c572257170e35d2227205458f099d73ca5da887102		 pdf-font-stream PDF embedded font (sfnt) at offset 0xF192 12708 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.