Malicious PDF — malware analysis report

Static analysis result for SHA-256 b370103583faf714…

MALICIOUS

PDF

70.4 KB Created: 2021-09-28 03:22:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 84710e4e82b1f7922594ef4afd836bf0 SHA-1: 85e67e0fc4b8d4f81e14a2e4b0360098f3844115 SHA-256: b370103583faf714c00782a326d42ab3d69430eca916170989b8cfe2095cff79
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs pointing to external domains, many of which appear to be disposable or used for hosting files. The 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicates a pattern of creating numerous links on low-reputation hosting, a common tactic for phishing or distributing malware. While no scripts were explicitly extracted, the presence of embedded URLs and the ML classifier's high confidence score suggest malicious intent, likely related to directing users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

Heuristics 5

  • 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://smidgel.ru/uplcv?utm_term=prayers+for+religious+leaders PDF link annotation
    • https://foundationkuzmanov.com/files/vevef.pdfIn PDF document text
    • http://brandiassociati.it/userfiles/file/vawivadi.pdfIn PDF document text
    • https://onsale.social-push.cc/data/fckeditor/files/95297409327.pdfIn PDF document text
    • https://minhvuongthuphap.com/upload/ck/files/57224499563.pdfIn PDF document text
    • http://hodinovysoused.cz/upload/file/juloxalubo.pdfIn PDF document text
    • https://china-glass-mosaic.vegner.com/userfiles/files/20210922_120219.pdfIn PDF document text
    • https://imihwa.com/uploads/image/20210904/files/20210904010044.pdfIn PDF document text
    • https://pbchistoryonline.org/uploads/file/nirogukuwuxakoniwegodu.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/16146425f72856---15550629579.pdfIn PDF document text
    • http://elfobchod.cz/foto/Image/file/32284297995.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614211e606c64---80244824612.pdfIn PDF document text
    • http://parilka.by/var/upload/file/pusebotifozi.pdfIn PDF document text
    • https://chuyennhakienvangvn.net/upload/files/lerepuzizetavarebeviru.pdfIn PDF document text
    • https://szabobuszrendeles.hu/files/files/ratiguvugipozon.pdfIn PDF document text
    • http://olympusflights.com/files/files/birofaginubak.pdfIn PDF document text
    • http://didongsinhvien.com/upload/files/42165471845.pdfIn PDF document text
    • http://beetsom.com/PROGRAM_FCKeditor_UserFiles/file/770754268614b664eedc02.pdfIn PDF document text
    • http://tangiahoang.vn/Images_upload/files/70086008796.pdfIn PDF document text
    • http://loveperfectionschool.com/upload/file/mawigizetulogimurigasenef.pdfIn PDF document text
    • http://24hnbc.com/assets/ckfinder/core/connector/php/uploads/files/badowagokob.pdfIn PDF document text
    • http://paddockj.com/user_data/editor/ckfinder/core/connector/php/upload/files/15042702810.pdfIn PDF document text
    • http://icbiz.ru/userfiles/file/rogesozomotakenilik.pdfIn PDF document text
    • http://mkngsp.ru/upload/files/12419082283.pdfIn PDF document text
    • https://dalton-english.com/userfiles/file/79138812558.pdfIn PDF document text
    • http://angel-conference.org/upload_fck/file/2021-9-25/20210925192449737364.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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b21a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB21A 16524 bytes
SHA-256: 6974595720f1777d6de3cfb0bd81e9e483f147d6de32ae03c1140e60d23a80e7
font_01_sfnt_off0000dc36.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC36 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f44d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF44D 10540 bytes
SHA-256: c8816aebe1cef57d9204d644c050680131a9cfcf6e8d5e9cc2abeb147300aa20