Malicious PDF — malware analysis report

Static analysis result for SHA-256 23e11a4da2a861b5…

MALICIOUS

PDF

75.0 KB Created: 2021-09-10 18:07:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: d420b9547a5eb2f4f3e68fa18ab97780 SHA-1: 39b45fdb0fcbdc6cff736375776aa626fba882cd SHA-256: 23e11a4da2a861b5a03b84555701132db714f23954a3ea2554ff1f90e31a77b8
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, many pointing to potentially malicious domains, suggesting a phishing or malware distribution scheme. While no scripts were explicitly extracted, the PDF structure and heuristic firings point towards an attempt to redirect users to external content, likely to exploit them further.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • 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 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://ozmutludokum.com/userfiles/file/tilife.pdf In PDF document text
    • https://sitycare.com/FCK-UserFiles/files/25911384871.pdfIn PDF document text
    • https://lee-trading.tw/archive/upload/files/70232889419.pdfIn PDF document text
    • http://sirinthepgroup.com/userfiles/file/64175651903.pdfIn PDF document text
    • http://toonesk.com/upload/40266520473.pdfIn PDF document text
    • http://restauraceeverest.cz/userfiles/file/kinizagujomirav.pdfIn PDF document text
    • http://conditum.nl/userfiles/file/88784050598.pdfIn PDF document text
    • http://factorycontrolprojects.com/userfiles/file/34842299130.pdfIn PDF document text
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/214b1058ff9d7d2d39ce37643f3231f2/vetufusaleliladosimubuse.pdfIn PDF document text
    • http://onlytech-tunisie.com/userfiles/file/48485080940.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16134f8e3a998a---38185844118.pdfIn PDF document text
    • https://rosycaffe.com/file/45897289007.pdfIn PDF document text
    • http://argyleliquidations.com/userfiles/files/63016631656.pdfIn PDF document text
    • http://huynhgiabaohotel.com/uploads/FCK/file/1657088133.pdfIn PDF document text
    • https://facades-et-traditions.com/actualites/file/monifolovop.pdfIn PDF document text
    • https://zweefvlieg.net/userfiles/file/vuximizurolebubi.pdfIn PDF document text
    • http://salman-is.com/userfiles/file/94530848969.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/17407530227.pdfIn PDF document text
    • http://webinaris.net/ckfinder/userfiles/publics/files/fibeposelefurez.pdfIn PDF document text
    • http://maasmartcity.com/userfiles/file/21636644845.pdfIn PDF document text
    • http://tabletopad.com/images/file/18184254439.pdfIn PDF document text
    • http://www.oneworldkarate.com/fckeditorimages/userfiles/file/7085972776.pdfIn PDF document text
    • https://cleaner.pl/userfiles/file/7347555908.pdfIn PDF document text
    • https://geelaboba.dswip.com/ci/userfiles/files/99439088628.pdfIn PDF document text
    • http://sangjeom.com/userfiles/file///71337599709.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=retrosynthesis+organic+chemistry+pdfPDF 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_off0000c140.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC140 16768 bytes
SHA-256: e40dfcbdc7c30caf292e240d9eff79517ed42862e80f99e134fc2e327b6dd318
font_01_sfnt_off0000ec02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC02 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010419.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10419 11180 bytes
SHA-256: 6de4649360c9fb9ee71ec12fd33109dd043d8b5ae3745c97a9ccb503c492a8eb