Malicious PDF — malware analysis report

Static analysis result for SHA-256 84665fc76dad2064…

MALICIOUS

PDF

41.4 KB Created: 2020-06-04 04:03:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 124313606146e5ef00e9f481a0b162c6 SHA-1: 609a701e1ca08179cb8f3ef7b4ab0997e326e9b5 SHA-256: 84665fc76dad20640f05e2be70b881b354914eb14c7ab0b76b98941a1edb1086
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was detected as malicious by ClamAV and an ML classifier, exhibiting characteristics of a dropper. It contains a large number of external links, many pointing to other PDF files, suggesting a link farm or distribution mechanism. The document body, though partially obfuscated, contains URLs that are likely part of this distribution strategy. The presence of a password archive lure heuristic indicates an attempt to bypass security controls.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 6

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • ClamAV: Pdf.Dropper.Agent-8854661-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Dropper.Agent-8854661-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://bandheadreunions.com/uploads/1/3/0/8/130874529/130874529.html#hoja+de+libreta+para+imprimir
    • http://multimodalresearchteam.com/uploads/1/3/0/3/130379227/3060771.pdf
    • http://jenniferwasmer.com/uploads/1/3/0/2/130270768/ba87cb03.pdf
    • http://sppslibrary.com/uploads/1/3/1/4/131406656/pizatode_rotixofalin.pdf
    • http://bandheadreunions.com/uploads/1/3/0/8/130874529/terms.html
    • http://bandheadreunions.com/uploads/1/3/0/8/130874529/dmca.html
    • http://bandheadreunions.com/uploads/1/3/0/8/130874529/policy.html
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://nulonexix.files.wordpress.com/2020/06/91700969430.pdf
    • https://gavadopojame.files.wordpress.com/2020/06/38187194517.pdf
    • https://popuxokogoju.files.wordpress.com/2020/06/87151275379.pdf
    • https://xulesik.files.wordpress.com/2020/06/ritibubuwitomilure.pdf
    • https://lalenej.files.wordpress.com/2020/06/55953494069.pdf
    • https://bemurizoz.files.wordpress.com/2020/06/40471271889.pdf
    • https://womemeb.files.wordpress.com/2020/06/32899208695.pdf
    • https://nuguvatun.files.wordpress.com/2020/06/lakigar.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005dbd.bin
a0a2503c1abaf1c5f5fcdeff4acc9c1358ba21153fd4d2b316f73e3d0a2a6aca
pdf-font-stream PDF embedded font (sfnt) at offset 0x5DBD 11288 bytes
font_01_sfnt_off000082e0.bin
3f70697d8cfd0b9becff5adcad726f9ffedcc5d773cc6f7abbcc82b2f8034994
pdf-font-stream PDF embedded font (sfnt) at offset 0x82E0 16164 bytes