Malicious PDF — malware analysis report

Static analysis result for SHA-256 95f2c23e32a288f3…

MALICIOUS

PDF

79.0 KB Created: 2020-04-20 08:38:05 +03:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6) First seen: 2020-09-24
MD5: 859d6456ab122efcd6eecefc6229d744 SHA-1: 94a62b61ee3394f42ef591bb2602a01515874cf8 SHA-256: 95f2c23e32a288f30b3bc1f5b992104b497a820c8c08f7d85277a71fa0ec8106
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous external links, a technique often used for SEO poisoning or to redirect users to malicious websites. The document body, though heavily obfuscated, suggests a lure related to 'combination circuits worksheet answers'. The heuristic 'PDF_SEO_LINK_FARM' indicates a large number of external links, pointing towards a malicious intent to drive traffic to potentially compromised or malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9892

Heuristics 4

  • 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.
  • 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://nypittysaviors.org/uploads/1/3/0/6/130620651/130620651.html#combination+circuits+worksheet+answers PDF link annotation
    • http://colororacle.com/uploads/1/3/1/3/131380845/wuzurikegufoletigimo.pdfIn PDF document text
    • http://spiritoasisdesigns.com/uploads/1/3/0/6/130621180/871474678cc8.pdfIn PDF document text
    • http://jeromeiwrightassociatesinc.com/uploads/1/3/1/6/131636988/porezutigozof.pdfIn PDF document text
    • http://elyadamscollection.com/uploads/1/3/0/7/130740173/pesusuvafixivo_silomug.pdfIn PDF document text
    • http://kaylinpound.com/uploads/1/3/0/7/130776434/be1c0.pdfIn PDF document text
    • http://lindarinehart.com/uploads/1/3/0/6/130639837/kefoxavodidet.pdfIn PDF document text
    • http://magicalmoscow.com/uploads/1/3/1/3/131384418/15b5950698.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • 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
    • https://fedoraproject.org/wiki/Licensing/LiberationFontLicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000105d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105D8 8124 bytes
SHA-256: fa0f1d24f53295f167394c23a08dc673f0c8be2d15203b80d68282d38287c8e8
font_01_sfnt_off00012539.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12539 2828 bytes
SHA-256: d8435aac11388b8214bfc980e857510ef47481ba706565f25bd6cae8efb01319