Malicious PDF — malware analysis report

Static analysis result for SHA-256 ba23b2c374faf5fc…

MALICIOUS

PDF

79.3 KB Created: 2021-09-13 18:13:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: eb2e8de188780d5e4efaab44d88a4d94 SHA-1: cefc40aad552f40aa0ddd1943e32df345f0f385d SHA-256: ba23b2c374faf5fc195049b5ccdd1929485a24ba379c601f2eca361ec8b8500e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The presence of numerous embedded URLs pointing to various PDF files suggests a link farm designed to distribute further malicious content or conduct phishing. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of a malicious document, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 http://z-i-f.ru/userfiles/file/wereweboga.pdf In PDF document text
    • https://tp-pos.com/uploads/image/files/lukosur.pdfIn PDF document text
    • https://dgssu.com/upfolder/e/files/20210907173100.pdfIn PDF document text
    • http://etkindenetim.com/resimler/files/60562070041.pdfIn PDF document text
    • https://greenways.at/userfiles/file/86802895590.pdfIn PDF document text
    • http://www.velkoobchod-man.eu/ckfinder/userfiles/files/40601843466.pdfIn PDF document text
    • http://clerus.hu/files/file/99405586115.pdfIn PDF document text
    • http://op-gold.com/ck_image/files/66927779831.pdfIn PDF document text
    • http://garmaclima.com/uploads/ckfinder/files/vevuroverugivuxo.pdfIn PDF document text
    • http://tobn56.com/UpFiles/file/78610900219.pdfIn PDF document text
    • http://schokoladenbrunnen.de/idata/13018254079.pdfIn PDF document text
    • http://kompassztuki.pl/Image/files/fegep.pdfIn PDF document text
    • http://ducthanggroup.com/webroot/img/files/3162220629.pdfIn PDF document text
    • https://wolfgang-photography.com/userfiles/files/giborof.pdfIn PDF document text
    • http://robertwestlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/pezunefeduwuxom.pdfIn PDF document text
    • http://chaitraglaze.com/uploads/lowulezawuwabimivute.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f88b64cda9---35036376816.pdfIn PDF document text
    • http://noithatlekhanh.com/Images_upload/files/17583219873.pdfIn PDF document text
    • http://asesoriazabalburu.org/azaba/files/file/70534099693.pdfIn PDF document text
    • https://tungafilm.com/dorceiys/ckfinder/userfiles/files/gonelag.pdfIn PDF document text
    • https://wlao.on.ca/wp-content/plugins/super-forms/uploads/php/files/3c19942c8a6d5ebd0d62447d4ebda7be/10200468867.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/1613affc2999cb---fovixexarigiz.pdfIn PDF document text
    • http://itena.si/uporabnik/file/59443560180.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=pubg+mobile+mod+unlimited+moneyPDF 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_off0000d3e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3E6 10516 bytes
SHA-256: f603e22cc29fa14d07dcc5935dbff3af8181546f153fdb8451c2beaf4e627f9a
font_01_sfnt_off0000eb92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB92 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000103a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103A4 17108 bytes
SHA-256: 68346c92757560a70e3c669a43234ff4a67f7b9ec17902d8eec9e36ffa2af7a8