Malicious PDF — malware analysis report

Static analysis result for SHA-256 39f45b6f4795238e…

MALICIOUS

PDF

49.2 KB Created: 2020-08-02 18:07:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1e7133a70cafc36acba13d4a78e85fe6 SHA-1: 01bf05d6d3e9f18552619732a38c5030253ae389 SHA-256: 39f45b6f4795238ef640db3c7358afccd6cf6ba4b6a6fffd1a362c6637cbea51
152 Risk Score

Malware Insights

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

The PDF contains a significant number of embedded links, with the primary URL pointing to a redirector known for malicious activity. The heuristic firings indicate this PDF is part of a link farm, likely intended to manipulate search engine results or distribute malicious content. The ML classifier strongly supports the malicious nature of this document.

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=english%20speaking%20daily%20use%20sentences%20pdf
    • http://files.borderpartnership.org/uploads/1/3/0/8/130873943/6414347.pdf
    • http://files.doulabianca.com/uploads/1/3/1/0/131070231/mubofim_xudevi.pdf
    • http://files.lhfieldfamilyfdn.org/uploads/1/3/1/3/131398091/6550427.pdf
    • http://files.itsyoursnapshot.com/uploads/1/3/1/8/131856454/ac7c0a5.pdf
    • https://cdn.shopify.com/s/files/1/0432/5523/4710/files/30144767053.pdf
    • https://cdn.shopify.com/s/files/1/0438/2982/1600/files/fopujapaloguroweduribu.pdf
    • https://cdn.shopify.com/s/files/1/0432/6152/6166/files/18166104283.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/62114329075.pdf
    • https://cdn.shopify.com/s/files/1/0438/3673/5645/files/10161374110.pdf
    • https://cdn.shopify.com/s/files/1/0430/7773/0464/files/wunawubat.pdf
    • https://cdn.shopify.com/s/files/1/0431/6187/8687/files/renolufomakiladozi.pdf
    • https://cdn.shopify.com/s/files/1/0437/7886/7351/files/78575570791.pdf
    • https://cdn.shopify.com/s/files/1/0438/8411/8171/files/devusi.pdf
    • https://cdn.shopify.com/s/files/1/0429/9689/1807/files/nopizofi.pdf
    • https://cdn.shopify.com/s/files/1/0435/4929/4756/files/mabon.pdf
    • https://cdn.shopify.com/s/files/1/0433/2745/5400/files/6138454034.pdf
    • https://cdn.shopify.com/s/files/1/0431/3215/8116/files/nedovolamigemokem.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_off000081f1.bin
a476cff9dca1dcccdc0b92e16d962b09d8a2a6c7c591caa526306248f4ea2efa
pdf-font-stream PDF embedded font (sfnt) at offset 0x81F1 5444 bytes
font_01_sfnt_off0000948e.bin
01a0126f83d59b066916d376bb2c1c400bd4f0e6dace7c905d99e392820f7908
pdf-font-stream PDF embedded font (sfnt) at offset 0x948E 10208 bytes