Malicious PDF — malware analysis report

Static analysis result for SHA-256 a56aa461be4d2591…

MALICIOUS

PDF

115.9 KB Created: 2021-03-25 10:57:26 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-22
MD5: 3273e30edf3aa4e865cb7215ee2e3a63 SHA-1: b7df95f15c86a54cbf59afa099ab8ffdd70d4752 SHA-256: a56aa461be4d2591d2ab9556b2b2ae923949ba4c420e9f238b7a7375749d6dc8
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, indicating a link farm or SEO spam tactic. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and numerous external URLs point towards an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • 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://midufefew.ru/award?keyword=bruckner+ave+maria+pdf PDF link annotation
    • http://getcreditreport.info/elna_supermatic_reviewmm8hq.pdfIn PDF document text
    • http://smartcreditscore.info/how_to_pair_2_jbl_partybox_100slez0.pdfIn PDF document text
    • https://cdn.sqhk.co/kisasizaro/eARhjIV/dota_underlords_ranking_system.pdfIn PDF document text
    • https://cdn.sqhk.co/zofagopipowi/zRjgjej/ace_combat_7_free_download.pdfIn PDF document text
    • https://zoxusikajikad.weebly.com/uploads/1/3/4/8/134851315/9385461.pdfIn PDF document text
    • https://cdn.sqhk.co/rasepotobami/djdMtgN/airplane_crash_today_florida.pdfIn PDF document text
    • https://vapevaka.weebly.com/uploads/1/3/1/4/131407737/4475062.pdfIn PDF document text
    • https://cdn.sqhk.co/lozosasuxe/iiSGBxu/43089970198.pdfIn PDF document text
    • https://rizowexerezo.weebly.com/uploads/1/3/4/2/134265486/1837889.pdfIn PDF document text
    • http://matroskin.space/les_miserables_look_down_lyrics8dfs7.pdfIn PDF document text
    • https://dirotigakavomak.weebly.com/uploads/1/3/4/2/134235834/19098ae70.pdfIn PDF document text
    • https://cdn.sqhk.co/tupuxinekowa/ifib0dK/steam_refund_game_over_2_hours.pdfIn PDF document text
    • http://sevastopol.sale/what_landforms_are_unique_to_australiag0hws.pdfIn PDF document text
    • https://cdn.sqhk.co/fewibefanid/djhiLii/bigfm_radio_livestream.pdfIn PDF document text
    • https://fugikoji.weebly.com/uploads/1/3/4/6/134611078/xuxujubafagu_vadosasitak_tuvajogukujis_logipu.pdfIn PDF document text
    • https://cdn.sqhk.co/zufuxirap/Up9DJgj/81347114553.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://12dd324c-696b-4d67-8c19-991f3eacec2c.filesusr.com/ugd/eeb7bd_cbb5b333797a438b9db1022c8e8e0699.pdf?index=trueIn PDF document text
    • http://niwapixezir.epizy.com/kigekosimederole.pdfIn PDF document text
    • http://gubodasitonobu.epizy.com/guzumefuwanuniku.pdfIn PDF document text
    • https://22e365c6-0853-42e1-82f8-83473bf9c0bf.filesusr.com/ugd/217d68_5a43189f79fd4121990cd8a8939df7d9.pdf?index=trueIn PDF document text
    • http://tesoduv.rf.gd/mudeloxam.pdfIn PDF document text
    • http://tuxumedef.epizy.com/31608032583.pdfIn PDF document text
    • https://5e20aa6b-77ef-4f11-9344-5454fb7c649c.filesusr.com/ugd/fb3aa9_49dc1ab676d445a89d240e0d2c225ccd.pdf?index=trueIn PDF document text
    • https://e691ad07-92dc-45fa-af10-8929b4045ede.filesusr.com/ugd/87b9a8_ae5013d584564d24949fa00345538010.pdf?index=trueIn PDF document text
    • https://a86a6b26-b473-4b55-b9aa-7628a2bff077.filesusr.com/ugd/4f270c_2313a9f890154b3bb1ff81e2873e9e1f.pdf?index=trueIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000184bf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x184BF 5264 bytes
SHA-256: b8469c534a5e5c94b3728128782d66c0110e81e5ca582b767a0fe1a88954be22
font_01_sfnt_off000196a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x196A2 13960 bytes
SHA-256: dbed4aa0355c23e026ef9b357acf26937eceb8b4544daebb91a38aeab3ed0d17