Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c91d7488bdc7cf9…

MALICIOUS

PDF

41.2 KB Created: 2020-08-20 18:09:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 7626cd6947fa66179d0585dbe48f08b5 SHA-1: c0fe3a9635f57f76f3ec4694756be9c30e6e2d1a SHA-256: 5c91d7488bdc7cf939ff57d76c72343a03757539d72c5ccc306deff4621a5dea
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file contains a significant number of embedded links, with one identified as a malicious redirector. The heuristic 'PDF_SEO_LINK_FARM' indicates a large number of external PDF links, suggesting an attempt to manipulate search results or distribute further malicious content. The ML classifier also strongly flagged this PDF as malicious. While no scripts were extracted, the presence of a malicious redirector URL and the link farm pattern points to a likely distribution or SEO poisoning 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.cc/pify?keyword=acg+guidelines+h.+pylori
    • http://files.carolinerovithi.com/uploads/1/3/0/7/130739318/sarevufinenavuno.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0450/0966/6212/files/woloxobunukosigono.pdf
    • https://cdn.shopify.com/s/files/1/0431/9058/3464/files/78071111022.pdf
    • https://cdn.shopify.com/s/files/1/0431/7760/7324/files/sociologie_de_l_ducation_cours.pdf
    • https://cdn.shopify.com/s/files/1/0430/4456/9242/files/7489287562.pdf
    • https://cdn.shopify.com/s/files/1/0431/1810/0637/files/dejawopizawoposolepakuki.pdf
    • https://cdn.shopify.com/s/files/1/0427/6443/5612/files/vinen.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/kubogofire.pdf
    • https://cdn.shopify.com/s/files/1/0432/2331/8686/files/64040755826.pdf
    • https://cdn.shopify.com/s/files/1/0430/7920/5013/files/41321525861.pdf
    • https://cdn.shopify.com/s/files/1/0433/1290/6405/files/sarezivizusamonixorane.pdf
    • https://medlineplus.gov/helicobacterpyloriinfections.html
    • 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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006559.bin
e2867b8921a00f434e3a4ca16d55c4893d3f8422e268aec73aa8c4acac3d3f90
pdf-font-stream PDF embedded font (sfnt) at offset 0x6559 5248 bytes
font_01_sfnt_off00007734.bin
5592628e0d160c28915484bf1af2661e44615f1e4151b244d22c3bb5847e9a21
pdf-font-stream PDF embedded font (sfnt) at offset 0x7734 9772 bytes