Malicious PDF — malware analysis report

Static analysis result for SHA-256 cde93295b8672fdd…

MALICIOUS

PDF

40.1 KB Created: 2020-08-09 15:54:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0e2874f1dd7dd5a7af7aa3f131774e97 SHA-1: 55b0e83b482465ec4395f1c9888a12f61e904ce2 SHA-256: cde93295b8672fdd500290fedbca6d44d8cb8a9d5f77028954909fc28a358c38
152 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 a redirector service (ttraff.ru) that is known to host malicious content. The document body, though heavily obfuscated, also contains the same redirector URL and other benign-looking PDF links, suggesting a link farm designed to lure users into clicking malicious URLs under the guise of academic resources. The ML classifier strongly supports the malicious verdict.

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=academic+word+list+synonyms+vietnamese+pdf
    • http://tidusol.drawingescapes.com/uploads/1/3/2/7/132740978/3432069.pdf
    • http://files.wanderingwildandfree.com/uploads/1/3/2/3/132302978/wixafum.pdf
    • http://files.cfolkensphotography.com/uploads/1/3/1/0/131070485/1704586.pdf
    • http://files.skynstyle.com/uploads/1/3/0/9/130969408/joxafaxexisuref_sewenuralo_famewilunudabu_migokidalarure.pdf
    • http://senowukun.chelseavt-arts.com/uploads/1/3/2/6/132681947/9126738.pdf
    • https://cdn.shopify.com/s/files/1/0429/8155/6375/files/complex_sentence_definition_and_examples.pdf
    • https://cdn.shopify.com/s/files/1/0433/0664/7717/files/lifecam_vx-_1000.pdf
    • https://cdn.shopify.com/s/files/1/0431/6761/3090/files/55978247257.pdf
    • https://cdn.shopify.com/s/files/1/0428/0595/2671/files/sarajamu.pdf
    • https://cdn.shopify.com/s/files/1/0432/9262/3001/files/wogitisunameka.pdf
    • https://cdn.shopify.com/s/files/1/0431/5525/9546/files/calendario_laboral_2020_baleares.pdf
    • https://cdn.shopify.com/s/files/1/0434/7455/0949/files/zisojuzikolirikojixavefir.pdf
    • https://cdn.shopify.com/s/files/1/0432/3760/5544/files/71893376514.pdf
    • https://cdn.shopify.com/s/files/1/0429/8014/7359/files/76820575561.pdf
    • https://cdn.shopify.com/s/files/1/0430/0688/6051/files/99004320227.pdf
    • https://cdn.shopify.com/s/files/1/0438/9657/0024/files/sadovukunudifeg.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_off00006051.bin
a432a7defdea094f5e3bab8225ee2193bcf8a448b0fc050eeeb37b290b9ee574
pdf-font-stream PDF embedded font (sfnt) at offset 0x6051 5544 bytes
font_01_sfnt_off00007332.bin
18210ad5fba0d40a910cd39c00b94e714a548413480f3bd4280fa81f40fb25d6
pdf-font-stream PDF embedded font (sfnt) at offset 0x7332 9480 bytes