Malicious PDF — malware analysis report

Static analysis result for SHA-256 714b95be83ad093c…

MALICIOUS

PDF

40.5 KB Created: 2020-08-31 14:46:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 638bde765cf8d01285f16632e604680b SHA-1: 60e8825ef3c6d0d3909a981d590aca10e6aaa465 SHA-256: 714b95be83ad093cb944bfa10e5b5c5940894701ce77fa2c35290b7934570c99
154 Risk Score

Malware Insights

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

The PDF contains a mass of external links, masquerading as a "British Council reading B1 PDF" to lure users. One of these links, https://ttraff.ru/wix?keyword=british+council+reading+b1+pdf, is identified as a malicious redirector. The ML classifier strongly indicates maliciousness, and the presence of numerous links suggests a link farm or SEO poisoning tactic to distribute further malicious content.

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/wix?keyword=british+council+reading+b1+pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/98e298_fe40273d8edb42dd902ca9267cfa71ff.pdf
    • https://static.usrfiles.com/ugd/b8c837_efecfac215454b0e9be89bf658fd3c9b.pdf
    • https://static.usrfiles.com/ugd/ae059d_bd64273f8ece466a8122263f92cfbcf4.pdf
    • https://static.usrfiles.com/ugd/b8c837_c89056227e6f45a3a5d8eed9a9e47951.pdf
    • https://static.usrfiles.com/ugd/69b86f_ccd193d1203245f2bdfa55013ff4b85c.pdf
    • https://cdn.shopify.com/s/files/1/0431/6784/2465/files/63556359649.pdf
    • https://cdn.shopify.com/s/files/1/0429/9925/1093/files/diloloviladareledazozap.pdf
    • https://cdn.shopify.com/s/files/1/0433/7680/3990/files/lodefiz.pdf
    • https://static.usrfiles.com/ugd/f4de5e_7bd6375352304c579b9af303692a001e.pdf
    • https://static.usrfiles.com/ugd/52b593_8d02685077b64e2e842bbf31e172747f.pdf
    • https://cdn.shopify.com/s/files/1/0429/9928/3861/files/symmetric_tree_leetcode.pdf
    • https://cdn.shopify.com/s/files/1/0430/3156/0354/files/nuguribagotusa.pdf
    • https://cdn.shopify.com/s/files/1/0435/1187/3688/files/wedamexafegomizuxaxus.pdf
    • https://cdn.shopify.com/s/files/1/0428/9898/1030/files/95076257303.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005d44.bin
c336f0f8a92694a33e9659d0517b74b1726640694c7083614a0a93d52b15d18a
pdf-font-stream PDF embedded font (sfnt) at offset 0x5D44 5660 bytes
font_01_sfnt_off00007086.bin
dd41e13e187da98747467c573423a8b634c428dec7bfd5bc00f6b26ff7155f98
pdf-font-stream PDF embedded font (sfnt) at offset 0x7086 11060 bytes