Malicious PDF — malware analysis report

Static analysis result for SHA-256 871724534c028bf0…

MALICIOUS

PDF

43.7 KB Created: 2020-08-29 19:56:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: dc794f271d0c87512e9e46468764a3ce SHA-1: 6156eec33bd27a35e7efcb0f984dc9461d20098b SHA-256: 871724534c028bf0d1df1dc0e24b8f103efe49ae7ff19efcf9fc9510c651bc2d
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, with one identified as a malicious redirector. The document body, though heavily obfuscated, appears to contain text related to academic subjects, suggesting a lure. The heuristic firings strongly indicate malicious intent through link manipulation and SEO spamming.

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.com/wix?keyword=naming+ionic+and+covalent+compounds+practice
    • https://static.usrfiles.com/ugd/80c1db_f98791702493450bb0663605a50ac0f5.pdf
    • https://static.usrfiles.com/ugd/b98abb_9873e29b049c4f58be674bb401fd769f.pdf
    • https://static.usrfiles.com/ugd/0c268c_f1d5179230be4aabac9b73d31f7eadb9.pdf
    • https://static.usrfiles.com/ugd/b8c837_25e3ad2c6eee427198d61bbb10038f25.pdf
    • https://static.usrfiles.com/ugd/3eed2b_a031852517b148559930ff9c72078920.pdf
    • https://static.usrfiles.com/ugd/b8c837_7a46cd2058f24d57ba087cc2f542a0bd.pdf
    • https://static.usrfiles.com/ugd/b8c837_6b64ec768100434e9636d97e258b2838.pdf
    • https://cdn.shopify.com/s/files/1/0437/8856/6677/files/mechanics_of_materials_7th_edition.pdf
    • https://cdn.shopify.com/s/files/1/0432/4907/4336/files/46536726212.pdf
    • https://cdn.shopify.com/s/files/1/0431/1053/1233/files/romumotagixovupepudi.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/sekokejeninidifowabofu.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/84005007378.pdf
    • https://cdn.shopify.com/s/files/1/0430/3601/6802/files/wekiturosiregejusev.pdf
    • https://cdn.shopify.com/s/files/1/0433/5842/1142/files/pdf_editor_free_download_blogspot.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_off00006d46.bin
c9cf59bbec42241a9aa574ac3ec5d56d37ba75de5ffb8454b9ca3afbbe9bba28
pdf-font-stream PDF embedded font (sfnt) at offset 0x6D46 5424 bytes
font_01_sfnt_off00007fa4.bin
a8fe5c7e829f5d9d9b4b93e3d9c81988acd10f2466cc9c5f469bde9f553f3ace
pdf-font-stream PDF embedded font (sfnt) at offset 0x7FA4 10004 bytes