Malicious PDF — malware analysis report

Static analysis result for SHA-256 acb18421d55b8d9a…

MALICIOUS

PDF

98.0 KB Created: 2021-09-20 06:16:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: d32fa8b47cc6d65a703a032e9ed232dc SHA-1: b5aa160e53e6d707e1671396cf6ee39264be1746 SHA-256: acb18421d55b8d9ad8e95d32818086da214db40bbc944a54502e57608b1e485d
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which are hosted on disposable domains, suggesting a link farm or phishing lure. The presence of PDF_SEO_DISPOSABLE_LINK_FARM heuristic further supports this, indicating a potential attempt to redirect users to malicious sites. No scripts were extracted, but the overall structure and URL patterns are indicative of a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9872

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://suavitinhtannha.net/upload/files/82580848662.pdf In PDF document text
    • http://rrbrentacars.com/files/others/4810872120.pdfIn PDF document text
    • http://aelma.com/sites/default/userfiles/file/metetalo.pdfIn PDF document text
    • https://blnk.eu/userfiles/files/gotit.pdfIn PDF document text
    • https://binhvi.com/upload/files/xiziwasuzajusu.pdfIn PDF document text
    • http://studiocinti.eu/userfiles/files/daxepibesabus.pdfIn PDF document text
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/9e349e57e6be595fc78991e2e229f2ff/fatasubegudokome.pdfIn PDF document text
    • http://sns.hu/_user/file/kenerilezew.pdfIn PDF document text
    • http://n2nnetworks.com/files/others/jemokafi.pdfIn PDF document text
    • http://benthanhsgfarm.com/images/uploads/files/nubatuxado.pdfIn PDF document text
    • https://coffotea.com/uploads/files/202109011218588427.pdfIn PDF document text
    • https://moderator.lt/components/com_mijoshop/opencart/image/data/files/dijakugiwil.pdfIn PDF document text
    • http://electriccityusa.com/images/fck_uploads/file/22569573981.pdfIn PDF document text
    • http://veitali.com/upload/files/bimewexaraf.pdfIn PDF document text
    • http://innotack.com/userfiles/file/siluzexejegivoterewodesi.pdfIn PDF document text
    • http://koddous.com/userfiles/file/44434045663.pdfIn PDF document text
    • https://bwhe.in/ckfinder/userfiles/files/16657777836.pdfIn PDF document text
    • http://phoiinnhiet.com/images/uploads/files/malezigikomevomo.pdfIn PDF document text
    • http://magic-mugs-factory.com/uploadfile/files/8217443543.pdfIn PDF document text
    • http://stressmanagement-karriere.de/userfiles/file/3992379591.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161478a4d2efe7---waluvuziledujutuwefu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=d%26d+monster+sheet+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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ecda.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECDA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000104e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104E7 2096 bytes
SHA-256: 6a5346a6d0f9af60a213d5141277f39e7c980664e59ed242a90b63afcd3915ff
font_02_sfnt_off00010e6a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E6A 9076 bytes
SHA-256: f695977626623e59fedb2fbedebd468d0acf89ff6f6ceafeb3cee4351ddee6c8
font_03_sfnt_off0001210b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1210B 25716 bytes
SHA-256: 0a56aa2e9b978f261697bb3b23a773ba90d53712c4a1c78ace5563caf69dd002
font_04_sfnt_off0001639f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1639F 16364 bytes
SHA-256: b91f250ecc59499bae01e5201042c58eb0c91b78753602ec7a55801858631810