Malicious PDF — malware analysis report

Static analysis result for SHA-256 eeed021c9fa3210b…

MALICIOUS

PDF

45.2 KB Created: 2020-08-13 02:49:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c542f1edce5e818e88e4ae016d8486de SHA-1: f02fbc0f12c52f994979f3d1d6ed898d1f3526ec SHA-256: eeed021c9fa3210b4f8cd287e0f16fda3d2f2ac9f6c3721ad9067e9674f39e2c
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, including one pointing to a known malicious redirector at 'https://ttraff.ru/wb?keyword=ctet%20answer%20key%202015%20pdf'. The document body, though partially corrupted, also contains this URL and appears to be a lure for exam-related content. The ML classifier strongly indicated maliciousness, and the presence of a link farm further supports a malicious intent to drive traffic to potentially harmful sites.

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/wb?keyword=ctet%20answer%20key%202015%20pdf
    • http://fanujik.integrativeneurostim.org/uploads/1/3/1/4/131408024/gufagiritem.pdf
    • http://zozajasos.thswebpages.org/uploads/1/3/1/1/131164250/fuwimawumifo.pdf
    • http://files.seattleanesthesia.net/uploads/1/3/1/3/131381722/nisurow.pdf
    • http://files.cit.org/uploads/1/3/0/7/130740264/fizabi_lonulupamawum.pdf
    • http://files.mintaddition.co.uk/uploads/1/3/1/6/131636903/7175770.pdf
    • https://cdn.shopify.com/s/files/1/0429/7929/5383/files/10252759557.pdf
    • https://cdn.shopify.com/s/files/1/0432/6853/8524/files/zusukutewovefedir.pdf
    • https://cdn.shopify.com/s/files/1/0437/8374/9781/files/lonimukobapekutalibagit.pdf
    • https://cdn.shopify.com/s/files/1/0431/7937/6798/files/sixixomugusibem.pdf
    • https://cdn.shopify.com/s/files/1/0437/3830/0568/files/78371601410.pdf
    • https://cdn.shopify.com/s/files/1/0437/7716/3426/files/kufapexitunemelogumutu.pdf
    • https://cdn.shopify.com/s/files/1/0429/1959/2099/files/kimedana.pdf
    • https://cdn.shopify.com/s/files/1/0437/5108/0090/files/tarewigexuzofu.pdf
    • https://cdn.shopify.com/s/files/1/0431/9870/9918/files/vovelo.pdf
    • https://cdn.shopify.com/s/files/1/0439/3893/9048/files/preguntas_del_ser_bachiller.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/sesolofulazige.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_off000071bb.bin
cb79dc3e3af6ce19f2a60a064bbc461004eee6c6efabb33f0ba1b8f1d1dc4f62
pdf-font-stream PDF embedded font (sfnt) at offset 0x71BB 5616 bytes
font_01_sfnt_off0000850b.bin
d2f29a4786f71eddffe375200360ecb68cf2adafeb52bbf91497fd71f5d6c9f0
pdf-font-stream PDF embedded font (sfnt) at offset 0x850B 10272 bytes