Malicious PDF — malware analysis report

Static analysis result for SHA-256 664e639c52325bd2…

MALICIOUS

PDF

85.0 KB Created: 2021-04-19 13:29:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 5a3cd058d4b15b324fe54766f07fa11b SHA-1: 8852710214d576cfd06316dbbd7c72f709fc27bc SHA-256: 664e639c52325bd260f6ce72ce04e5cb9dc38ea38a343c24839c403b0226672f
226 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a remote-support lure. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 7

  • 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.
  • Remote-support tool lure high SE_REMOTE_SUPPORT_LURE
    Document instructs the user to install, open, or connect with a remote-support tool such as AnyDesk, TeamViewer, Quick Assist, or ScreenConnect — high-risk in an unsolicited document
  • 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://mezovuduw.ru/strik?utm_term=vnc+server+android+no+root PDF link annotation
    • https://nudiwosesi.weebly.com/uploads/1/3/4/3/134317077/nufejixewog_gewusulipejuzu_tojev.pdfIn PDF document text
    • https://pufokebisuniga.weebly.com/uploads/1/3/5/3/135324869/sevovizak.pdfIn PDF document text
    • http://napowojeba.medianewsonline.com/definition_of_marketing_by_different_authors.pdfIn PDF document text
    • https://forilulan.weebly.com/uploads/1/3/1/4/131408022/9914a.pdfIn PDF document text
    • http://markettop.pro/handwriting_analysis_test_online_free8jziy.pdfIn PDF document text
    • https://nolujamikudaze.weebly.com/uploads/1/3/4/8/134868466/a823c8db65e.pdfIn PDF document text
    • http://xuxikurov.mygamesonline.org/arthritis_back_exercises.pdfIn PDF document text
    • http://organicnu.info/94054159151dmg9w.pdfIn PDF document text
    • https://xebolusuzibukun.weebly.com/uploads/1/3/4/5/134506512/tapex_puleguvefime_lugamusa_zefep.pdfIn PDF document text
    • http://whalesqpa.fun/how_to_do_formalist_criticism0n02b.pdfIn PDF document text
    • http://ens-pictures.ru/85425997610cxruq.pdfIn PDF document text
    • http://kerosijuvibeg.scienceontheweb.net/64158607166.pdfIn PDF document text
    • https://bufudelazevel.weebly.com/uploads/1/3/4/7/134734798/tizasisuti.pdfIn PDF document text
    • https://refirumalot.weebly.com/uploads/1/3/4/6/134603215/latitizegi-wekurifaf.pdfIn PDF document text
    • https://makirogu.weebly.com/uploads/1/3/0/9/130969002/segafi.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://eee5dff6-7331-416e-acdf-593d0c386862.filesusr.com/ugd/21e9e0_047ba47b1db34f37869094dd2b317792.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/gawabog/77899835821.pdfIn PDF document text
    • https://s3.amazonaws.com/minaxigevani/libro_espaol_lecturas_segundo_grado_primaria_sep.pdfIn PDF document text
    • https://s3.amazonaws.com/resixexi/breakup_status_video.pdfIn PDF document text
    • https://ddd59a73-be73-4575-bd7b-2e5900175f8b.filesusr.com/ugd/5dc0ef_7f1a144cbb204c5ab2d4fffba5aaf237.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/liguwubore/blancanieves_cuento_de_los_hermanos_grimm.pdfIn PDF document text
    • https://s3.amazonaws.com/mipeboro/how_to_use_a_prophet_sport_lipo_charger.pdfIn 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ff66.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF66 4716 bytes
SHA-256: bd42bc7f83ff73b6dc214a526df2daaf2a0cc34c99c327df685c7e796bed04a1
font_01_sfnt_off00010f69.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F69 12252 bytes
SHA-256: fce67d1c85b8478370db9d7be7b52cd1b3eefef1d0faac298c09b7512a51d9c0
font_02_sfnt_off000137f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137F0 4324 bytes
SHA-256: cd94ef65598b1866d0653cdd88243d989fd81359c0e770c2d3a4858f1c2f6d34