Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf7681fcb39a531a…

MALICIOUS

PDF

51.0 KB Created: 2020-06-09 21:45:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ef24041b8a761b2fa0b17a44aa1bb8e5 SHA-1: 9b5ba5b31b4a2d767e9f458614a39660640c2e39 SHA-256: cf7681fcb39a531abc59d486b933bf1c1f2ea4df130415b7aa5c6a4322347b9c
94 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by an ML classifier. It contains a large number of external links, many pointing to similarly structured URLs on various domains, indicating a link farm. The document body contains text related to 'Riskmed soru bankas1', suggesting a lure, possibly related to educational or professional testing materials. The primary attack pattern involves redirecting users to these external sites, which could host further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

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://mazorcasdecolombia.com/uploads/1/3/1/4/131455247/131455247.html#riskmed+soru+bankas%25C4%25B1
    • http://annaslavicgallery.com/uploads/1/3/0/7/130775297/femejetiz_wixorawo_tolibuju_kemosidaxej.pdf
    • http://equilibriumacupuncture.co.uk/uploads/1/3/0/7/130776257/mogub.pdf
    • http://autodiscover.mgmhaberdashery.com/uploads/1/3/0/7/130775104/5453844.pdf
    • http://ctaincnc.com/uploads/1/3/0/7/130739182/7c8aad.pdf
    • http://itssniakay.com/uploads/1/3/0/9/130969768/d8880e4fe47f.pdf
    • http://assessmenttest.info/uploads/1/3/0/6/130621570/xurozaponisixilejifa.pdf
    • http://gonzalesprimarycare.com/uploads/1/3/0/7/130738753/2341016.pdf
    • http://hostmaster.garbagedisposal.us/uploads/1/3/1/3/131380745/b066e02f.pdf
    • http://ebricksandmortar.com/uploads/1/3/0/3/130379482/9246293.pdf
    • http://rjsbuilding.designpreviewer.com/uploads/1/3/0/6/130604896/3756777.pdf
    • http://pedestalproductions.com/uploads/1/3/1/0/131071289/ef91d901c68.pdf
    • http://randeeot.com/uploads/1/3/0/7/130739379/3a75f97d8c.pdf
    • https://xilukikebop.files.wordpress.com/2020/06/3889368566.pdf
    • https://tudavolo.files.wordpress.com/2020/06/19499764856.pdf
    • https://jejasefepu.files.wordpress.com/2020/06/zijuje.pdf
    • https://nojurax.files.wordpress.com/2020/06/zobamarisilul.pdf
    • https://jezofisuwoma.files.wordpress.com/2020/06/boduwevulibagegon.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/

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007585.bin
c4af3ac90c751da980461fbc3215ec6e7dde56ef0216eeef2c9718b0eece9647
pdf-font-stream PDF embedded font (sfnt) at offset 0x7585 1572 bytes
font_01_sfnt_off00007d83.bin
fe36f23039d01ca534e672b3d31b5dd66adf0bf11d3b06fd1f37c386f095b337
pdf-font-stream PDF embedded font (sfnt) at offset 0x7D83 13940 bytes
font_02_sfnt_off0000a81b.bin
c988415812f594187b0a0ed75dc52802e798e1695b49bd300f8412a65040a449
pdf-font-stream PDF embedded font (sfnt) at offset 0xA81B 16204 bytes