Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7892ecf925c1dea…

MALICIOUS

PDF

81.4 KB Created: 2021-04-16 05:21:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ddebd8734a181efed6d6a78e3c1d06eb SHA-1: 4e880ad8169a8da7be19268bd3014aa60aaa3829 SHA-256: a7892ecf925c1deaf83ae78cbab2b0ec4f48e6585823ad24f86b110cf3706521
156 Risk Score

Malware Insights

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

This PDF file is identified as malicious by multiple heuristics and an ML classifier, indicating a phishing or trojan-like behavior. It contains a large number of external links, many of which point to other PDF files, suggesting a link farm or SEO poisoning tactic to distribute malicious content. The primary URL, 'https://zajinet.ru/strik?utm_term=free+download+piano+sheet+music+for+beginners', is presented as a lure for free sheet music, likely to mask the malicious intent of redirecting users to other potentially harmful documents.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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://zajinet.ru/strik?utm_term=free+download+piano+sheet+music+for+beginners
    • https://cdn.sqhk.co/mudifuto/gc0NdrO/twisted_metal_ps4_cheats.pdf
    • https://jogemubo.weebly.com/uploads/1/3/4/3/134321321/975bdc5f66b3e.pdf
    • https://runuxufugax.weebly.com/uploads/1/3/0/9/130969308/1045525.pdf
    • https://cdn.sqhk.co/pajokiman/ThbjeX1/69540131013.pdf
    • http://dadosib.22web.org/bade_bhai_sahab_chapter_question_answers.pdf
    • https://static.s123-cdn-static.com/uploads/4451556/normal_5fe4d8ecadb4e.pdf
    • https://cdn.sqhk.co/wedegetuso/xhihfJy/easy_street_free_the_life_sims.pdf
    • https://wofexajolevesi.weebly.com/uploads/1/3/5/3/135302186/b945453599c29e5.pdf
    • http://mosubulopig.iblogger.org/forward_biased_diode.pdf
    • https://cdn.sqhk.co/kokizoxujojo/ajhakia/extent_report_version_4_tutorial.pdf
    • https://cdn.sqhk.co/kefimuriw/fhfjcif/crashlands_mission_guide.pdf
    • https://cdn-cms.f-static.net/uploads/4474752/normal_5fe9c4e9b0f38.pdf
    • https://cdn-cms.f-static.net/uploads/4413573/normal_606e6aa3f2ffc.pdf
    • https://static.s123-cdn-static.com/uploads/4383165/normal_6002fe7ac3fa6.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/dafumuxitupav/66604373629.pdf
    • https://28481333-1ef2-46fb-8ebf-d56c3f24acbc.filesusr.com/ugd/314c35_fe1531b79d174126b994059d254208c1.pdf?index=true
    • https://s3.amazonaws.com/ravuxudibure/57167266428.pdf
    • https://s3.amazonaws.com/xojafemori/performance_evaluation_report_form_pakistan.pdf
    • https://s3.amazonaws.com/resabomibogodaw/kahlil_gibran_il_profeta_matrimonio.pdf
    • https://f59c0a4d-c104-43ac-8966-a5978cdf1b8c.filesusr.com/ugd/0c1ebd_f93a5a0e488948ab86cfb07cf7c5b1b7.pdf?index=true
    • https://s3.amazonaws.com/kujesulad/530048111.pdf
    • https://12f7643e-9106-4823-89c2-0bdaecd1bc22.filesusr.com/ugd/1f6d71_f9fe308793aa466f9594ba453df9843f.pdf?index=true
    • https://fb79ad55-22b5-4823-9538-35c71bbbd514.filesusr.com/ugd/ea423f_d06140b10d734353aa83a49f38ad650d.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fdfa.bin
1dd657f6c4bbb0b1a482f5b620f8c8968fe897174d9aab9e3b9777a5d05bf3d1		 pdf-font-stream PDF embedded font (sfnt) at offset 0xFDFA 5756 bytes
font_01_sfnt_off00011179.bin
f74fd411e0b08eab15ab3f19248dd633ad13fb4e79a04954b7ffe4fbc6e1aaff		 pdf-font-stream PDF embedded font (sfnt) at offset 0x11179 11232 bytes

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