Malicious PDF — malware analysis report

Static analysis result for SHA-256 a99581d177b193c2…

MALICIOUS

PDF

27.4 KB Created: 2018-06-11 08:58:42 -04:00 Authoring application: wkhtmltopdf 0.12.4 (via Qt 4.8.7) First seen: 2020-08-10
MD5: 1b41371af54552f61d5c7e1d94913125 SHA-1: a204d1b7a1a499a7f6205c225bdd25f78a2dfe74 SHA-256: a99581d177b193c2e44c55e3df829ac41fbbd206dd52d9afad32d18856b5bbb4
130 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious File

The PDF file contains embedded URLs pointing to 'uncpbisdegree.com', which are flagged as suspicious and likely serve as download locations for malicious payloads. The presence of a 'download button' heuristic and the ML classifier's high confidence score further support a malicious intent. The document body, though partially garbled, suggests a lure related to an owner's manual, aiming to trick the user into downloading a file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9664

Heuristics 4

  • Fake 'free download' SEO-poisoning PDF critical PDF_SEO_FAKE_DOWNLOAD
    The ML classifier flagged this PDF AND it carries a visual download/call-to-action lure AND an off-domain server-side download-gateway link whose query string names a document payload. This three-signal conjunction is the fake-document / 'free PDF download' SEO-poisoning delivery pattern: the page is padded with benign decoy links to dilute classifier scores while funnelling the victim through the gateway to malware/scareware. Acting only on the conjunction keeps benign download-bearing PDFs from being misflagged.
  • PDF carries a PHP-gateway SEO-spam PDF link farm medium PDF_SEO_PHP_GATEWAY_LINK_FARM
    PDF contains four or more clickable links whose target is a `.php` gateway with a multi-word search-PHRASE document slug embedded after it (e.g. 'index.php?.../binary+options+trading+nz.pdf' or 'pdf.php/cialis-dosage-side-effects.pdf'). Legitimate PHP-served documents use a filename or numeric id, not a search-query phrase, so this is the generated SEO link-farm shape — pharma / binary-options / 'free download' spam that ranks for queries and routes users into payload/redirect chains. The PDF itself carries no exploit — the risk is the linked destinations.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://uncpbisdegree.com/download3.php?q=sharp-lc-26d42u-tvs-owners-manual.pdf In PDF document text
    • http://uncpbisdegree.com/download4.php?q=sharp-lc-26d42u-tvs-owners-manual.pdfIn PDF document text
    • http://riverside-resort.net/1/volvo-s60-2001-owners-manual.pdfIn PDF document text
    • http://riverside-resort.net/1/water-for-all-series-2-poverty-and-water-security-understanding-how-water-affects-the-poor.pdfIn PDF document text
    • http://uncpbisdegree.com/1/tests-elements-of-literature-sixth-course-page-71-answer-key.pdfIn PDF document text
    • http://riverside-resort.net/1/wiley-solutions-manual-biological-physics.pdfIn PDF document text
    • http://riverside-resort.net/1/yukon-denali-navigation-manual.pdfIn PDF document text
    • http://riverside-resort.net/1/what-is-cannabis-oil-good-for.pdfIn PDF document text
    • http://uncpbisdegree.com/1/textbook-rental-ontario.pdfIn PDF document text
    • http://riverside-resort.net/1/yamaha-motorcycle-user-manual.pdfIn PDF document text
    • http://riverside-resort.net/1/when-was-the-earth-made.pdfIn PDF document text
    • http://uncpbisdegree.com/1/the-broken-word.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://go.microsoft.com/fwlink/?LinkId=521839&CLCID=0409In PDF document text
    • http://go.microsoft.com/fwlink/?LinkID=246338&CLCID=0409In PDF document text
    • https://go.microsoft.com/fwlink/?linkid=868922In PDF document text
    • http://go.microsoft.com/fwlink/?LinkID=286759&CLCID=409In PDF document text
    • http://go.microsoft.com/fwlink/?LinkID=617297In PDF document text
    • https://fedoraproject.org/wiki/Licensing/LiberationFontLicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00003107.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x3107 10164 bytes
SHA-256: dc9455d9313df672e5d325004b583634b4a3c40cff21243cf6c38b1e2de4d50c
font_01_sfnt_off0000515c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x515C 7312 bytes
SHA-256: 925b413c5959979d8c4a4d331de7a87d3a486e43d1d272c132f8c11472d35dce

Open this report in the interactive analyzer, or submit your own file for analysis.