Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fbb350e6e949d60…

MALICIOUS

PDF

42.5 KB Created: 2020-08-05 04:47:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 24f103b2d6fcb6a0e4c3c77fc9506930 SHA-1: fa33f688a0d9cc13f0c4b532e050b5fa583db3bf SHA-256: 8fbb350e6e949d60c62e8173622cffb9dde3e8fbc6e9cb633900796f2e7b42c3
154 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to external PDF files hosted on various domains, including a known malicious redirector. The heuristic 'PDF_MALICIOUS_REDIRECTOR_LINK' indicates that at least one of these links directs to malicious infrastructure. The ML classifier also strongly flagged this PDF as malicious. The document body appears to be corrupted or obfuscated, but the presence of the malicious redirector URL suggests a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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 https://ttraff.ru/pify?keyword=perspectiva+de+genero+definicion+pdf
    • http://files.natashabrussell.com/uploads/1/3/1/4/131411411/mumiwamalazozi.pdf
    • http://files.ahwatukeecommunitycenter.com/uploads/1/3/2/7/132740435/3108801.pdf
    • http://files.asaap.us/uploads/1/3/2/7/132710683/9384976.pdf
    • http://files.gallery.allie-coosh.com/uploads/1/3/0/7/130775025/3910126.pdf
    • http://files.fcadefuniak.com/uploads/1/3/1/4/131409264/2089233.pdf
    • https://cdn.shopify.com/s/files/1/0433/6166/5192/files/zilujopinuvodetefemowajif.pdf
    • https://cdn.shopify.com/s/files/1/0430/9165/6864/files/wimubapimo.pdf
    • https://cdn.shopify.com/s/files/1/0430/2651/4077/files/bawesexotadaderuruji.pdf
    • https://cdn.shopify.com/s/files/1/0435/2350/6336/files/ninupamusimovejutefawuk.pdf
    • https://cdn.shopify.com/s/files/1/0429/6241/9863/files/fewadi.pdf
    • https://cdn.shopify.com/s/files/1/0431/5083/5876/files/madinedibelos.pdf
    • https://cdn.shopify.com/s/files/1/0433/3905/5253/files/13098655545.pdf
    • https://cdn.shopify.com/s/files/1/0433/7192/1571/files/39949195888.pdf
    • https://cdn.shopify.com/s/files/1/0437/3941/4677/files/16695398092.pdf
    • https://cdn.shopify.com/s/files/1/0430/9755/5093/files/drivers_license_renewal_texas.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000658f.bin
6a5c3519152ca993ae8bfdff018d0cbf4f3730108050ec6dd81d609fc49a3a58
pdf-font-stream PDF embedded font (sfnt) at offset 0x658F 5352 bytes
font_01_sfnt_off000077df.bin
f7d26c6af6cdc6224df7052820838d92b3045b290439607a2acfc48e8754de4e
pdf-font-stream PDF embedded font (sfnt) at offset 0x77DF 10900 bytes