Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac317bb555b63c1e…

MALICIOUS

PDF

82.2 KB Created: 2021-04-09 23:58:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: a43f8a53bcf499dcecfb95e2ebdaa117 SHA-1: b0becb09bdac94e45b13c495a6ad4bd38fb00769 SHA-256: ac317bb555b63c1e3485e112a4c24c7be97ae2d12d6a616204f599ecac6e3e1b
186 Risk Score

Malware Insights

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

This PDF file was identified as malicious by ML classifiers and ClamAV. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm or phishing operation. The embedded URLs, such as 'https://pelibifir.ru/strik?utm_term=maxi+cosi+mico+ap+limited+edition+capsule', are likely used to redirect users to malicious sites. Although no scripts were explicitly extracted, the PDF structure and extensive link farm indicate an attempt to distribute malware or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

Heuristics 6

  • 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
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://pelibifir.ru/strik?utm_term=maxi+cosi+mico+ap+limited+edition+capsule
    • https://cdn-cms.f-static.net/uploads/4459163/normal_5fd9a2a65d5b0.pdf
    • http://rarubife.mygamesonline.org/is_smart_board_software_free.pdf
    • http://3gusevshop.space/746793806838xqf1.pdf
    • http://beviluxenumiliv.mywebcommunity.org/general_aptitude_for_gate_exam.pdf
    • https://povemiloten.weebly.com/uploads/1/3/4/6/134608376/wibuginaseg.pdf
    • http://getallcreditscores.info/93297695404715mk.pdf
    • http://tumuduwaju.mypressonline.com/dipuw.pdf
    • https://dewofawofuzujo.weebly.com/uploads/1/3/0/7/130775987/8374125.pdf
    • http://suporefebakibur.mygamesonline.org/dinike.pdf
    • https://kobuxomibusopi.weebly.com/uploads/1/3/4/6/134609859/d0a8358.pdf
    • https://cdn-cms.f-static.net/uploads/4446923/normal_6050641f30b02.pdf
    • https://cdn-cms.f-static.net/uploads/4484097/normal_605f96a3ab12c.pdf
    • http://borejukeluteva.mygamesonline.org/what_does_informal_imperialism.pdf
    • https://kasasifu.weebly.com/uploads/1/3/4/6/134697732/f76859ef.pdf
    • https://static.s123-cdn-static.com/uploads/4369322/normal_6001e488d18a4.pdf
    • https://rewusimivizegan.weebly.com/uploads/1/3/4/5/134578415/repuwi.pdf
    • http://zunuruxeguxifi.mygamesonline.org/54013484256.pdf
    • https://cdn-cms.f-static.net/uploads/4467273/normal_602495e524238.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • http://www.daltonmaag.com/
    • https://f84ffea9-2755-49c2-9cb5-47ca8b55fe65.filesusr.com/ugd/0adedf_21394b811cf84b22bfc25163eb2fff87.pdf?index=true
    • http://luregaw.onlinewebshop.net/77643041259.pdf
    • https://f19d2187-ce67-4d04-8798-eef694565169.filesusr.com/ugd/bd4746_5efc8a86e36044009fcb7aebc6eb4c98.pdf?index=true
    • https://0e627107-309b-4451-a84d-e7064c41fccd.filesusr.com/ugd/04c368_ad5fa1aa25074ea5af6b2b6b810ee60a.pdf?index=true
    • http://logiweliziweje.onlinewebshop.net/public_relations_officer_duties.pdf
    • http://desejole.myartsonline.com/la_recherche_du_temps_perdu_2011_tv_film.pdf
    • https://0e098354-e5d1-4afc-9be7-763a70ae5e44.filesusr.com/ugd/ef253e_d74deec62153417fa4998e94ee54702f.pdf?index=true
    • https://4900ecec-7ac1-411c-be2c-b077674085c8.filesusr.com/ugd/493135_aadc71fe4a7a4e0e8996000f597864fb.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_off0000f36a.bin
bd77f6d7c92471ce663ca582908143782582afa8c81a7fecf2e531b01992a4f2
pdf-font-stream PDF embedded font (sfnt) at offset 0xF36A 5076 bytes
font_01_sfnt_off0001049e.bin
a10c6f8342c5370a6b7af5b07f0cc33abae9046e6c309bc9c32c17f54b8a4358
pdf-font-stream PDF embedded font (sfnt) at offset 0x1049E 11440 bytes
font_02_sfnt_off00012abc.bin
b50a2106bf82917db0cd3cf88f63c5e8cc3298b343ace5cffc591b35df33d24c
pdf-font-stream PDF embedded font (sfnt) at offset 0x12ABC 4324 bytes