Malicious PDF — malware analysis report

Static analysis result for SHA-256 fbb0e143856ab93d…

MALICIOUS

PDF

81.1 KB Created: 2021-09-19 19:17:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: c2d3246df52d32bfcadf9b2e4122951f SHA-1: d01e53ca604082501e7e8f05aeeb0855a94be682 SHA-256: fbb0e143856ab93d76303bcf9996ebe21f866b62a65ba824e0aa2baac948d729
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 pointing to external PDF files hosted on various domains, suggesting a link farm or redirection mechanism. The heuristic PDF_SEO_DISPOSABLE_LINK_FARM indicates a high volume of links to disposable hosting, reinforcing the malicious intent. While no scripts were explicitly extracted, the nature of the embedded URLs and the detection as a phishing trojan points towards an attack pattern involving luring users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://kargiskola.ge/myadmin/ckeditor/ckfinder/userfiles/files/69495649498.pdf In PDF document text
    • http://palirna-frydek.cz/uploaded/file/boxogubepazik.pdfIn PDF document text
    • http://cheapneasytrafficschool.com/CheapNEasyTrafficSchool/pa/trainstation/uploads/image/file/47896918914.pdfIn PDF document text
    • http://cjmfgxfollow.morefriendship.com/upload/files/laboma.pdfIn PDF document text
    • http://www.emporiocaritaspisa.it/wordpress/wp-content/plugins/formcraft/file-upload/server/content/files/16138c7081427a---sozuwibadabowu.pdfIn PDF document text
    • https://www.ikedatosou.com/wp-content/plugins/formcraft/file-upload/server/content/files/161341a197da08---10407368448.pdfIn PDF document text
    • http://orlickachata.cz/files/files/35654517987.pdfIn PDF document text
    • http://influences-vegetales.eu/assets/Image/files/58186672538.pdfIn PDF document text
    • https://holcom-wd.holcom.vn/webroot/img/files/mubirimesifu.pdfIn PDF document text
    • http://tavio.su/files/file/jejapejonobitijadufonev.pdfIn PDF document text
    • http://screen.by/images/file/xalivu.pdfIn PDF document text
    • http://milwaukee.center/userfiles/file/64774306798.pdfIn PDF document text
    • http://flashdisplay.net/UploadFiles/FCKeditor/20210904152519.pdfIn PDF document text
    • http://dailymaydemtien.com/userfiles/files/turapudin.pdfIn PDF document text
    • http://insfilings.com/skyzone_classic/upload/files/76880224441.pdfIn PDF document text
    • http://the100voicesofgospel.de/fichiers/newsletter/file/29008641611.pdfIn PDF document text
    • https://cihangirhotel.com/upload/ckfinder/files/3708659629.pdfIn PDF document text
    • http://wsystem.sk/userfiles/files/40415830483.pdfIn PDF document text
    • https://asfus.net/virgsurv/userfiles/file/75792261467.pdfIn PDF document text
    • http://matsonconstruction.net/userfiles/file/safunuronokilonip.pdfIn PDF document text
    • https://idealist.ro/userfiles/file/wadavisagadosox.pdfIn PDF document text
    • http://heaig.org/editor/ckfinder/userfiles/files/gesisipopusotekizuf.pdfIn PDF document text
    • http://nesemlak.com/test/images/uploads/files/10510703326.pdfIn PDF document text
    • http://vino-charlie.cz/userfiles/file/levivujikofigomesov.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=the+platform+full+movie+online+free+englishPDF 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_off0000db2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB2A 16384 bytes
SHA-256: 7ebd2d93f5bb4424c602ca5a88cda2682815738808421c8f4a74a5765fa5ed4d
font_01_sfnt_off00010547.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10547 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011d5e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D5E 10932 bytes
SHA-256: 505f8a85d0c6e601b9a7af0995d56e9ce471eec32b38b6bb02e9f03363f4b25b