Malicious PDF — malware analysis report

Static analysis result for SHA-256 373b0e7b19b2befc…

MALICIOUS

PDF

77.1 KB Created: 2021-09-17 02:05:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: bce2a9ee0c7d509d3fdde259779cf41d SHA-1: 6abdec21096aa8656ef9545ed479ccdf5855bc71 SHA-256: 373b0e7b19b2befce7c80daa964ce0ebf32299367a5d4cf87013bd08ad1db38a
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 of which point to suspicious domains, suggesting a link farm or redirection mechanism. While no scripts were explicitly extracted, the PDF structure and the presence of external links are indicative of a phishing or malware distribution lure, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9919

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://cubic.is/userfiles/file/59450549986.pdf In PDF document text
    • http://krzeptowski.pl/file/gixavanorakenaxegegifube.pdfIn PDF document text
    • http://dh-cell.net/ckfinder/userfiles/files/39655401365.pdfIn PDF document text
    • http://csc010.com/userfiles/file/20210909220327_49zk6k.pdfIn PDF document text
    • https://dancleland.com/img/upload/file/gizuwe.pdfIn PDF document text
    • https://otterdisplay.com/userfiles/file/lojexivawaxibonazemoxeve.pdfIn PDF document text
    • http://moonlightmontessori.com/upload/files/junolepobodad.pdfIn PDF document text
    • http://alda.pl/ckfinder/userfiles/files/71924554586.pdfIn PDF document text
    • https://highfieldhousehotel.net/nbloom/fckuploads/file/37224765777.pdfIn PDF document text
    • http://zehanbiopharma.com/upload/files/pulefugisa.pdfIn PDF document text
    • http://wannawwannie.pl/userfiles/file/28610053989.pdfIn PDF document text
    • http://boekenwinkelindex.nl/images/uploads/6540694658.pdfIn PDF document text
    • http://g-shocktou.com/user_file/file/45384142986.pdfIn PDF document text
    • https://calmoinc.com/upload/editor/file/62576266265.pdfIn PDF document text
    • http://gachbinhduong.com/upload/file/9116392197.pdfIn PDF document text
    • https://thaiwoodengames.com/files/upload/files/10388974634.pdfIn PDF document text
    • http://enidental.com/userfiles/file/20210915204520.pdfIn PDF document text
    • https://mavismanagement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613729f60499f---42612354391.pdfIn PDF document text
    • http://mtjjt.com/2013/upload/article/files/210914120509134186k4fu3.pdfIn PDF document text
    • http://gdlejia.com/uploadfile/files/20210913_031529.pdfIn PDF document text
    • https://brazilairporttransfers.com/ckfinder/userfiles/files/34153097094.pdfIn PDF document text
    • https://www.hotelamoha.it/wp-content/plugins/formcraft/file-upload/server/content/files/161312e77c8472---sumupefewu.pdfIn PDF document text
    • https://sinarlangit1.com/contents/files/janagufiniponuwotemoj.pdfIn PDF document text
    • http://kmconlinecme.com/userfiles/file/41127462557.pdfIn PDF document text
    • https://hongmao.tw/uploads/files/202109070836546440.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/3CAf4wW3hvY/uplcv?utm_term=similar+to+kodiPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b464.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB464 17812 bytes
SHA-256: 2e2caf82e53ed8fb38e83b245d357e8b9bda716c0ca54b37e2f4e9bdd96e5f2c
font_01_sfnt_off0000cfbc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCFBC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e7d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7D3 10172 bytes
SHA-256: 1e362e501d676b4f7e79018a7012ba00159ee54ead22a46ced43ca96d0fbdd66
font_03_sfnt_off0000fe8b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE8B 15704 bytes
SHA-256: a0b8d92a396558cf50af4aad5873fb8036ef298916b4850e181685924db2afee