Malicious PDF — malware analysis report

Static analysis result for SHA-256 be8ac1b1690b2b8a…

MALICIOUS

PDF

91.0 KB Created: 2021-09-09 19:54:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: d92c478a89e83c35464327d83001c749 SHA-1: a6e2168d1a1e6066aeef298366d65e9d8ed0cd5a SHA-256: be8ac1b1690b2b8a17357c303e6edee4fa73bd3ac20a465954cf4cbf10adf93f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are hosted on potentially disposable domains and appear to be part of a link farm. ClamAV and an ML classifier flagged this PDF as malicious, specifically as a phishing trojan. While no scripts were explicitly extracted, the PDF structure and embedded links suggest an intent to redirect users to malicious sites, likely for phishing or to download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

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 http://yhbinternational.com/userfiles/file/nupupidusog.pdf In PDF document text
    • https://www.gullyracing.it/admin/ckfinder/userfiles/files/wufajijenuzofubiwiromax.pdfIn PDF document text
    • http://alpha-th.com/userfiles/file/61998130432.pdfIn PDF document text
    • http://bluecars.pl/userfiles/file/jukumi.pdfIn PDF document text
    • http://mgtuae.com/uploads/file/10480865730.pdfIn PDF document text
    • https://ssekolkata.com/ckfinder/userfiles/files/nogitekazimonorup.pdfIn PDF document text
    • https://foodphotoshop.com/userfiles/files/sizeru.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/16134f71d3dbaa---51553612252.pdfIn PDF document text
    • https://eastmangroupllc.net/ckfinder/userfiles/files/7232407802.pdfIn PDF document text
    • https://www.bevillelecomte.com/ckfinder/userfiles/files/61897899522.pdfIn PDF document text
    • http://congluc.com/upload/files/89037099892.pdfIn PDF document text
    • http://bdsductri.com/upload/files/33585389038.pdfIn PDF document text
    • http://another-partner.morefriendship.com/upload/files/61122685990.pdfIn PDF document text
    • http://ks-system.co.uk/ckfinder/userfiles/files/tomutisezopivonakemuxok.pdfIn PDF document text
    • http://fszhenjia.com/upfolder/e/files/20210909063426.pdfIn PDF document text
    • https://drbumbnursinghome.in/ckfinder/userfiles/files/litawuteverivilona.pdfIn PDF document text
    • http://auswallendorf.de/userfiles/file/17437286783.pdfIn PDF document text
    • https://netcsemege.elelmiszer-hazhozszallitas.hu/ckfinder/userfiles/files/tilosev.pdfIn PDF document text
    • https://edukiya.com/wp-content/plugins/super-forms/uploads/php/files/c09a49770456947d378070f947ccfb49/leweledixusuvidilu.pdfIn PDF document text
    • http://cukorbetegshop.hu/files/wosibumodoresonew.pdfIn PDF document text
    • https://big-affaires.com/img/pics/files/jumujilapidexaxutat.pdfIn PDF document text
    • http://cosmik-kinoteatr.ru/sadm_files/litebexa.pdfIn PDF document text
    • http://laboratoriodiprogettazione-ve.it/userfiles/files/kovuboxodororax.pdfIn PDF document text
    • https://kenkochaya.com/user_data/ckfinder/files/zibokixajorukujeve.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3CAf4wW3hvY/uplcv?utm_term=how+to+run+react+native+app+in+emulatorPDF link annotation
    • 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_off0000f9b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9B6 20024 bytes
SHA-256: ae15446c4fc3fa54b21033e60282123aeab96ecf0492b525ded583f357e16529
font_01_sfnt_off00012e3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12E3C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014653.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14653 10608 bytes
SHA-256: c86e85b4cc98dcb7236974489aa0f9b4fd83a3814fd1546e909a164c214680f6